INSTRUCTION MANUAL

S-8000 SERIES HIGH RESOLUTIONFEB CD MEASUREMENT SEM

(SYSTEM SECTION)(V11 ~)

Please read through this manual carefullyand store it in a safe place.

···· Before using the instrument, read thesafety instructions and precautionscarefully.

···· Keep this manual in a safe placenearby so it can be referred towhenever needed.

Copyright ã Hitachi, Ltd. 1998. All rights reserved. Printed in Japan. Part No. 567-8220

Notice:

1. Information contained in this document is subject tochange without notice for improvement.

2. No part of this manual may be reproduced ortransmitted in any form or by any means without theexpress written permission of Hitachi.

3. Hitachi assumes no liability for any direct, indirect, orconsequential damages arising from use notdescribed in this manual.

4. This document does not provide any warranty orpermission for industrial properties or any rights togrant license lawfully and without infringement.

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FOREWORD

Thank you very much for purchasing the Hitachi S-8000 Series High Resolution FEB CDMeasurement SEM. It is designed for carrying out circuit pattern inspection and dimensioncontrol in evaluation of semiconductor device fabrication processes. Please read throughthis manual carefully for long-lasting trouble-free operation of the instrument.

HOW TO USE THIS INSTRUCTION MANUAL

• The instruction manuals for the S-8000 Series High Resolution FEB CD Measurement SEMinclude the following three volumes; System Section , Operating Section and WindowOperation Section . This volume of instruction manual is System Section .

• The System Section covers the installation requirements, names of parts of instrument,functions and operating principles, file system, coordinate schemes, start/stop of instrumentoperation, troubleshooting, maintenance, safety precautions, etc.

• The Operating Section presents the instrument operating procedures, file creatingprocedures, optional function control procedures, and possible causes of error messagesand remedial procedures.

• The Window Operation Section deals with the operational functions and procedures forwindows displayed on the monitor.

• Before attempting operation of the instrument, read the System Section first. Then, afteryou have acquired a basic knowledge of the instrument system, proceed to the OperatingSection and Window Operation Section .

• The maintenance and checkup procedures for ensuring normal operation of the instrumentare described in the System Section . According to the periodic check list, carry outmaintenance and inspection periodically as instructed.

• This instruction manual contains descriptions of more than one instrument model, softwareversion and optional function in some items. Check your instrument model, softwareversion and optional functions incorporated, read the relevant descriptions.

• This instruction manual covers the following models of S-8000 series.S-8000 series: S-8820/S-8620, S-8840/S8640

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GUARANTEE

Period of Guarantee

One year from the date of installation.

Details of Guarantee

The instrument will be repaired free of charge if it malfunctions due to a defect in manufacturewithin the period of guarantee and this is acknowledged by Hitachi.

Unguaranteed Items

This guarantee will not be valid for the following failures and/or cases even during the period ofguarantee.

· Failure due to use in improperly installed condition

· Failure caused by erroneous use or improper repair

· Failure attributable to movement or relocation after installation

· Failure resulting from disassembly or modification by customer

· Failure due to force majeure such as fire or earthquake

· Consumables and parts limited in period of guarantee

· The guarantee period of the electron source (tip) of S-8000 series is 6000 hours or ninemonths, whichever earlier, and is excluded from the one-year guarantee.

· The guarantee period of the electron source (tip) of S-7800 is 4000 hours or six months,whichever earlier, and is excluded from the one-year guarantee.

· Remarkably hastened corrosion of electric circuits and deterioration of optical elementsdue to corrosive gases (chlorine gas, etc.) contained in air.

· When instrument is disposed of or resold without informing Hitachi.

· When instrument is disassembled, modified or subjected to parts replacement withoutHitachi’s approval, or re-installed without informing Hitachi.

INSTALLATION AND AFTER-SALES SERVICE

Installation at delivery will be carried out by our installation engineers. For the installation, besure to refer to section 1. Installation at another place after delivery will be provided atcharge. To avoid possible trouble involved in relocation, be sure to consult your nearestHitachi service representative. And for service after the guarantee period, please consult usabout a maintenance & inspection contract.

SAFETY - 1

SAFETY SUMMARY

General Safety Guidelines

Before operating the instrument, read the following instructions carefully:

• Follow all the operating procedures provided in this manual.

• Pay special attention to and follow all the hazard warnings on the instrument and in themanual. Failure to do so can cause injury to yourself or damage to the instrument.

• The hazard warnings which appear on the warning labels on the instrument or in themanual have one of the following alert headings consisting of an alert symbol and a signalword, DANGER, WARNING, or CAUTION.

DANGER : indicates an imminently hazardous situation which, if notavoided, will result in death or serious injury.

WARNING : indicates a potentially hazardous situation which, if notavoided, can result in death or serious injury.

CAUTION : indicates a hazardous situation which, if not avoided, will orcan result in minor or moderate injury, or serious damage ofproduct.

: The alert symbol shown at left precedes every signal word forhazard warnings, and appears in safety related descriptions inthe manual.

The signal word ‘NOTICE’ is used to present warnings which are not directly related topersonal injury hazards.

• Do not perform any operation or action in any way other than as provided in this manual.When in doubt, call the designated field engineer.

• Keep in mind that the hazard warnings in this manual or on the instrument cannot coverevery possible case, as it is impossible to predict and evaluate all circumstancesbeforehand.Be alert and use your common sense.

SAFETY - 2

WARNING

• Voltages up to 100 V AC and 10 kV DC are used insidethis instrument. Do not touch inside or you mayreceive an electric shock.

• Do not remove the covers of main column unit, controlunit or power unit while the instrument power is turnedon. There is a danger of fatal or serious injury due toelectric shock.

• Anyone working on the electrical part of the systemshould follow the correct lock-out tag-out procedures forthat location.

• Electrical hazards can occur if lock-out tag-outprocedures are not followed.

CAUTION

Beware of injury

• There is a possibility of injury while the wafer transfermechanism is operating.

• Do not touch inside the cassette loader with the powerturned on.

SAFETY - 3

WARNING

1. Beware of invisible laser

• An invisible laser is used in this instrument.Looking directly at the laser beam or coming intocontact with it may result in injury.

• Upon opening the cover of the Z sensor, an interlockmechanism works to prevent oscillation of the laser.But before opening this cover, be sure to turn OFF eitherthe SEM power switch at the top of the display unit or theZ sensor key switch.

2. This instrument is equipped with the laser device shownbelow. Under normal operation, there is no potentialfor accidents since it is not required to take out the laserdevice. To ensure safety, however, be sure to observethe following precautions.

(1) Never touch the laser beam emitting/receiving partmounted in the column unit.

(2) Never touch the laser drive circuit mounted on thespecimen chamber.

(3) When the laser device has reached the end of itsservice life, refer replacement/adjustmentservicing to Hitachi service personnel. Do nottamper with the laser device. Remember thatother optical parts also are not user-serviceable.

Conforming to ANSI Z136.1-1985

3. Never adjust or use the laser control function in amanner not specified in this instruction manual, or youmight be exposed to the laser beam.

Designation Wavelength Output Class of Output Purpose InsideInstrument

Semiconductorlaser

780 nm (red) 5 mW max. Class 3B(3 to 500 mW)

Detection ofspecimen height

SAFETY - 4

WARNING

• If a large amount of vaporized hexane (n-hexane) isinhaled, it may result in injury or breathing difficulty.

• In a place where hexane is used, be sure to ventilatewell and be careful not to inhale in a large amount.Also wear an antigas mask or the like if necessary.

• Be careful not to ignite vaporized hexane because itmay explode.

• When hexane is used, be sure to ventilate the place welland don't use a flame in the vicinity.

• If hexane is mistakenly swallowed or comes into contactwith the skin or eyes, it may affect the nervous systemin various ways such as paralysis of the senses,difficulty in walking, etc. due to stimulation.

• When hexane is used, be sure to ventilate the placewell, and depending on the conditions, use an airaspirator, protective goggles and protective gloves andclothes.

CAUTION

• Gazing at the CRT screen and/or operating the keyboard for long hours may result infatigue or other ill effects.

• The customer is recommended to establish work management standards and followthem.

SAFETY - 5

CAUTION ON DISPOSAL OF INSTRUMENT

• Although at present the instrument does not use materials that will directly harm theenvironment, changes are apt to be made in relevant laws and/or regulations, so be sureto consult a qualified specialist when planning to dispose of the instrument.

PRECAUTIONS ON USERange of application

• The instrument is intended mainly for measuring and observing linewidths and patternson semiconductors.

Operator qualification

• Operation should be conducted under the management of a technician who hasundergone orientation at the facility specified by Hitachi.

Caution on use and maintenance

• For usage and maintenance of the instrument, use the specified procedure and avoidtouching any place other than specified.

Environmental requirements (installation conditions)

• Follow the specified installation conditions.

• Do not lift the instrument via its table when moving it.

• When relocating the instrument, be sure to fasten the console with the brackets used at transportation.

• Contact the sales agent for change of the installation place.

Warning labels maintenance

• Call your nearest Hitachi service representative.

SAFETY - 6

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S-8000 SERIES HIGH RESOLUTIONFEB CD MEASUREMENT SEM (SYSTEM SECTION)

(V11~)

CONTENTS

1. INSTALLATION ......................................................................................................... 1–11.1 Installation Requirements ................................................................................. 1–1

1.1.1 General ................................................................................................. 1–11.1.2 Room Temperature and Humidity.......................................................... 1–21.1.3 Line Power Requirements ..................................................................... 1–21.1.4 Grounding ............................................................................................. 1–21.1.5 Gas Source ........................................................................................... 1–31.1.6 Stray Magnetic Field.............................................................................. 1–31.1.7 Vibration ................................................................................................ 1–41.1.8 External Power/Electric Field Noise....................................................... 1–41.1.9 Disturbance by Sound Waves ............................................................... 1–41.1.10 Physical Requirements

(Installation space, entrance dimensions, floor conditions).................... 1–51.1.11 Power Capacitance ............................................................................... 1–101.1.12 Evacuation Duct for Oil Rotary Pump (option)........................................ 1–10

1.2 Items to Be Prepared by User........................................................................... 1–121.3 Power and Ground Wiring Connections............................................................ 1–13

2. FUNCTIONS.............................................................................................................. 2–12.1 Appearance of Instrument System.................................................................... 2–12.2 Specifications ................................................................................................... 2–2

2.2.1 Specifications of S-8840/S-8640 ........................................................... 2–22.2.2 Specifications of S-8820/S-8620.............................................................. 2–4

2.3 Main Column Units ........................................................................................... 2–62.3.1 General ................................................................................................. 2–72.3.2 Evacuation System................................................................................ 2–82.3.3 Evacuation Control (Manual) Panel ....................................................... 2–92.3.4 Auto Loader System.............................................................................. 2–152.3.5 Objective Movable Aperture Control ...................................................... 2–19

2.4 Display Unit ...................................................................................................... 2–202.4.1 Appearance of Display Unit ................................................................... 2–202.4.2 Functions............................................................................................... 2–20

2.5 Power Supply Unit ............................................................................................ 2–262.5.1 General ................................................................................................. 2–27

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CONTENTS (cont’d)

3. PRINCIPLE OF MICROSCOPE INSTRUMENT......................................................... 3–13.1 Schottky Emission (SE) Electron Source .......................................................... 3–13.2 Electron Optical System ................................................................................... 3–2

3.2.1 Retarding Method.................................................................................. 3–23.2.2 Note on Retarding Method Operation.................................................... 3–3

3.3 Two-Stage Detection System (S-8840/S-8640) ................................................ 3-4

4. COMPUTER SYSTEM AND SOFTWARE ................................................................. 4–14.1 Computer System Configuration....................................................................... 4–1

5. FILES......................................................................................................................... 5–15.1 System Files ..................................................................................................... 5–15.2 User Files ......................................................................................................... 5–2

5.2.1 Hierarchical File Structure ..................................................................... 5–35.2.2 Handling of User Files ............................................................................. 5–4

6. COORDINATE SCHEMES ........................................................................................ 6–16.1 General............................................................................................................. 6–16.2 Stage Coordinate Scheme................................................................................ 6–16.3 Wafer Coordinate Scheme ............................................................................... 6–2

6.3.1 Chip Number and On-Chip Coordinates ................................................ 6–26.3.2 Wafer Coordinates ................................................................................ 6–3

6.4 Wafer Alignment............................................................................................... 6–46.5 Visual Field Shift in Each Coordinate Scheme.................................................. 6–6

7. STARTUP AND SHUTDOWN OF INSTRUMENT ..................................................... 7–17.1 Startup.............................................................................................................. 7–1

7.1.1 Usual Startup Procedure ....................................................................... 7–17.1.2 Startup from Complete Shutdown.......................................................... 7–37.1.3 Startup After Recovery from Power Failure or Emergency Stop............ 7–5

7.2 Shutdown of Instrument.................................................................................... 7–57.2.1 Normal Shutdown.................................................................................. 7–57.2.2 Complete Shutdown of Instrument ........................................................ 7–67.2.3 Shutdown at Power Failure.................................................................... 7–7

8. IMAGE ADJUSTMENT .............................................................................................. 8–18.1 Optical Microscope Image ................................................................................ 8–1

8.1.1 Adjustment of Optical Microscope (OM) Image ..................................... 8–18.1.2 Auto Adjustment of Optical Microscope (OM) Image............................. 8–3

8.2 Condition Setting for SEM Image...................................................................... 8–4

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CONTENTS (cont’d)

8.3 Axial Alignment of Electron Optics.................................................................... 8–58.3.1 Axial Alignment of Electron Optics......................................................... 8–58.3.2 Axial Alignment of Electron Gun (carried out by service engineers only)8–68.3.3 Axial Alignment of Condenser Lens 1 and 2

(carried out by service engineers only) .................................................. 8–78.3.4 Axial Alignment of Objective Movable Aperture ..................................... 8–78.3.5 Axial Alignment Using Alignment 1........................................................ 8–88.3.6 Axial Alignment Using Alignment 2........................................................ 8–98.3.7 Axial Alignment of Stigmator Coil .......................................................... 8–98.3.8 Astigmatism Correction ......................................................................... 8–98.3.9 Focusing................................................................................................ 8–108.3.10 Saving/Loading of SEM Condition Memory ........................................... 8–128.3.11 Image Contrast and Brightness ............................................................. 8–12

9. TROUBLESHOOTING............................................................................................... 9–19.1 Evacuation System Abnormalities..................................................................... 9–39.2 Abnormal Specimen Stage/Loader ................................................................... 9–49.3 Abnormal SEM Image....................................................................................... 9–6

9.3.1 Abnormal Emission Current................................................................... 9–69.3.2 Absence of Image on CRT .................................................................... 9–69.3.3 Noisy Image .......................................................................................... 9–7

9.4 Abnormal Optical Microscope (OM) Image ....................................................... 9–89.4.1 Absence of OM Image........................................................................... 9–8

9.5 Display Unit Fails .............................................................................................. 9–89.6 Software Error ................................................................................................. 9–8

9.6.1 How to Save Log Data onto Hard Disk (HD).......................................... 9–99.6.2 How to Output Log Data onto Floppy Disk............................................. 9–99.6.3 Restart After Software Error .................................................................. 9–10

10. MAINTENANCE......................................................................................................... 10–110.1 Consumables and Spare Parts ......................................................................... 10–1

10.1.1 Consumables ........................................................................................ 10–110.1.2 Spare Parts ........................................................................................... 10–2

10.2 Cautions on Maintenance ................................................................................. 10–210.3 Periodic Inspection ........................................................................................... 10–3

10.3.1 Evacuation System................................................................................ 10–410.3.2 Replacement of Objective Movable Aperture......................................... 10–510.3.3 Check Lists............................................................................................ 10–710.3.4 Rotary Vacuum Pump (option) .............................................................. 10–11

INDEX................................................................................................................................. I-1

1 - 1

1. INSTALLATION

1.1 Installation Requirements

If the following installation requirements are not satisfied, consult Hitachi about countermeasures.

1.1.1 General

For installation of this instrument, avoid the conditions listed below. Refer to 1.1.6 through1.1.9 for details.

(1) Room located in the vicinity of transformer substation

(2) Room in the vicinity of elevator

(3) Location near large-power consuming equipment (e.g. electric furnace) or its power supply

(4) Location near spark discharge source or high-frequency apparatus (5) Room filled with gas which may corrode metals

(6) Place exposed to strong draft

(7) Location subjected to severe vibrations

(8) Use of ground line common to other electrical equipment

(9) Location near radio or sound wave source

1.1.1

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1.1.2 Room Temperature and Humidity

At a place where this instrument is installed, maintain the following environmental conditionseven when it is not operated.

(1) Room temperature •••••20 to 25°CTemperature fluctuation should be less than 2°C during operation of the instrument.

(2) Humidity (RH) •••••60% or lessThe instrument should be operated in an air-conditioned room.

1.1.3 Line Power Requirements

(1) 100 V AC, 5 kVA, 50/60 Hz, 1 phase (Maximum power: 100 V AC, 50 A)It is required to supply power continuously.Even if the instrument is left unused for a long time, evacuation should be performedcontinuously.Fluctuation in line power voltage should be within a range of ±10% with respect to 100 VAC level.

NOTICE: For a period of 24 hours, power voltage fluctuation should be within a range of±5%, and no abrupt fluctuation on the order of seconds is allowable.

(2) Momentary power interruption should be restricted to less than one cycle at 100% DIP.

(3) The power supply unit of this instrument should be located within a distance of 10 metersfrom the power distribution panel on wall (the input AC power cord is 10 meters long).The solderless terminal is equipped at the end of the input AC power cord.(Solderless terminal size: 8.6 mm in inside diameter, 16 mm in outside diameter)

(4) On the power distribution panel, be sure to use a circuit breaker dedicated for thisinstrument.It is required to supply primary input power protection for isolation transformer not toexceed 250% (12,500 VA for S-8000 series, S-7800) of power ratings.

1.1.4 Grounding

Connect this instrument with a grounding terminal having ground resistance of less than100 ohms. The grounding terminal must not be common to other electrical equipment, i.e. anexclusive grounding connection to earth should be provided.

1.1 Installation Requirements

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1.1.5 Gas Source

(1) N2 Gas Source (for leak)

Gas pressure : 400 to 880 kPa (4 to 9 kgf/cm2), with 0.01 µm filterOutside diameter ofconnecting tube : 6 mm

(2) Compressed Air Source (for valve drive)Air pressure : 600 to 880 kPa (6 to 9 kgf/cm2)Outside diameter ofconnecting tube : 6 mm

(3) Vacuum Source (for auto loader)Vacuum pressure : P = 13 to 40 kPa (100 to 300 Torr)Diameter of connecting tube: 6 mm

1.1.6 Stray Magnetic Field

No image trouble will occur when the stray magnetic field conditions shown in Tables 1-1 aresatisfied at the instrument installation place. Before proceeding to installation, check the straymagnetic field conditions as required. Make sure that the conditions shown in these tables aresatisfied.If there is a large-sized magnet clutch or power cable for other equipment in the vicinity of thisinstrument, abrupt variation in current or magnetic field may take place. Avoid installing thisinstrument at such a location.If the instrument is installed in an environment having intense stray magnetic field, the scanningelectron beam is forced to tremble due to the magnetic field, causing abnormal expansion,shrinkage, distortion, unintentional shift, or whisker noise in imaging. These adverse effectsoccur differently depending on whether the frequency component of stray magnetic field issynchronous with power current frequency or not. Therefore, the allowable value of straymagnetic field component synchronous with power current frequency is different from that ofstray magnetic field component asynchronous with power current frequency (DC magnetic fieldvariation).

(1) Adverse effects due to stray magnetic field component synchronous with power frequency,and its maximum allowable value:The stray magnetic field component synchronous with power frequency appears as imagedistortion or deformation on the CRT display. This is because the electron beam isscanned in synchronization with the power frequency.The maximum allowable value of stray magnetic field component synchronous with powerfrequency is specified so that no adverse effect will be given to CD measurementreproducibility.

1.1.5

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(2) Adverse effects due to stray magnetic field component asynchronous with powerfrequency, and its maximum allowable value:The stray magnetic field component asynchronous with power frequency affects imagingdirectly. That is, movement of the electron beam due to variation in external magneticfield appears as unintentional shift or whisker noise in imaging. Even slight variation inexternal magnetic field may result in conspicuous irregularity of image.The maximum allowable value of stray magnetic field component asynchronous with powerfrequency is specified so that CD measurement reproducibility will not be affected byimage shift or whisker noise due to stray magnetic field.

1.1.7 Vibration

Before installing this instrument, measure floor vibration at site. No image trouble will occurwhen the vibration conditions shown in Tables 1-2 and 1-4 are satisfied.If the instrument is installed on the first floor of a reinforced-concrete (steel-framed-concrete)building, the performance of instrument will not be degraded by external vibration as long asvibration sources such as heavy-duty machine tools or transportation facilities (e.g. electric car)are not operated nearby.Check the vibration conditions at site before installation (or on receiving order) as required.Make sure that the conditions shown in these tables are satisfied. (As to vibrationmeasurement at site, consult Hitachi sales representative.)

1.1.8 External Power/Electric Field Noise

To prevent a possible trouble in imaging, check for any interference noise source in selection ofan installation place for this instrument. If such an interference noise source as shown in Table1-5 or its power line is located nearby, it will cause poor imaging. Also, a desirable image maynot be attained if an interference noise source even located at a distance consumes large power.Besides, if a device located nearby or its power line uses a different commercial powerfrequency from that for this instrument, the power-frequency-synchronized scanning will bedisturbed. Remember this in selection of an installation place.

1.1.9 Disturbance by Sound Waves

Sound waves (vibrations of air) will adversely affect this instrument and may cause imagetrouble. To prevent this, make sure before installation that a sonic disturbance source is notlocated nearby.If there is any sonic disturbance source in the vicinity of the installation place, then check fornoise level. When conversation is possible in a usual voice around the installation site, thenoise level is allowable. But if conversation is possible only in a loud voice due to abnormalnoise of equipment located nearby, sonic disturbance will occur in imaging.

Allowable sound pressure: Less than 75 dB (in C characteristic)

1.1 Installation Requirements

1 - 5

1.1.10 Physical Requirements(Installation space, entrance dimensions, floor conditions)

(1) Floor Space Required (excluding the space areas for operation, maintenance and powersupply equipment)Approx. 3.0 m (W) ´ 2.2 m (D) recommended

(2) Dimensions of Entrance1.8 m (W) ´ 2.2 m (H) at least

(3) Durability of Floor

(4) Installation LayoutRefer to Figs. 1-1 through 1-3.

(5) Maintenance Spaces for InstrumentBe sure to leave the following maintenance spaces (including easy-to-open partitions).Main column unit : Front, rear and left-side space areas for maintenanceControl unit : Front and rear space areas for maintenancePower supply unit : Front and rear space areas for maintenance

Table 1-1 Allowable Stray Magnetic Field (At CD measurement)

SEM Operating Conditions for CD MeasurementStray MagneticField ComponentSynchronous withPower Frequency(AC magnetic field)*1, *2

Stray Magnetic FieldComponentAsynchronous withPower Frequency(DC magnetic fieldvariation) *3

AcceleratingVoltage

ObservationMagnification

SpecimenScanning

Mode

0.3 mT or less 0.1 mT or less 800 V 40,000´ Resist L/S AVER mode,frame number 8

T: Tesla (104 gauss)

Notes: *1. The components due to terrestrial magnetic field are excluded from the value indicatedabove.Terrestrial magnetic field in Japan:

Horizontal magnetic component • • • 30 mTVertical magnetic component • • • • • 35 mT

*2. An effective value of AC component should be measured.*3. If DC magnetic field variation is 0.1 mT or less, it may be out of consideration when observing

intensity-modulated images.

3

Floor strength (kg/m2)³

Floor area of room (m2)

Total weight of instruments installed in room (kg)

1.1.10

1 - 6

Table 1-2 Allowable Vibration

External vibration: No image trouble will occur if the following conditions are satisfied.

(1) Oscillation frequency of less than 10 Hz

NOTICE: 1. A sine wave should be measured in vibration measurement. In case of other than asine wave, measurement should be made with each frequency component concentrated ata dominant frequency* level.

2. For vibration at extremely low frequency of less than 1 Hz, complete prevention isimpossible with the vibration-isolating technology available at present.

3. In a frequency region of 2 Hz to 10 Hz, interpolation should be made through each allowablevalue point.

4. If floor vibration exceeds the allowable limit, please consult Hitachi (floor vibration that maycause any image trouble should be measured in advance).

(2) Oscillation frequency exceeding 10 HzIf the dominant frequency of oscillation exceeds 10 Hz, please consult Hitachi.

* Dominant frequency: Peak frequency upon subjecting the oscillation waveform to frequency analysis.

Oscillation Frequency Amplitude

1 Hz 3 mm p-p max.

2 Hz 0.7 mm p-p max.

3 Hz 1.2 mm p-p max.

4 Hz 2 mm p-p max.

5 Hz 3 mm p-p max.

10 Hz 3.5 mm p-p max.

1.1 Installation Requirements

1 - 7

Table 1-3 External Noise Sources (Interference power/electric field noise sources)

Classification Possible Cause ofInterference Noise

Noise Source Equipment

Electric device withcontacts

Electric discharge(spark, arc)

Flashing signal device, relay,electromagnetic conductor,thermostat

Equipment driven bycommutator motor

Electric discharge(spark, arc), slidingcontact

Electric drill, vacuum cleaner

Electric discharge tube Glow discharge Neon discharge tube, high-pressure mercury arc lamp

Small-sized electricequipments(general/homeelectrical appliances)

Control unit havingsemiconductor devices

Phase control(transient) noise

Thyristor dimmer, inverter

Industrial high-frequency equipment

Disturbance signal* Industrial high-frequencyheater, high-frequencyelectric welder, etchingequipment

Medical high-frequencyequipment

Disturbance signal* VHF/UHF treatmentapparatus

High-frequencyfacilities

Ultrasonic-waveequipment

Disturbance signal* Flaw detector, ultrasoniccleaner

High voltage, largecurrent

Induction of commercialpower frequency(electrostatic induction,electromagnetic induction,current leak to ground)

Power cable (powertransmission line)

Electric discharge(corona, arc)

Corona noise, poor insulator,poor contact due to corrodedmetal (arc discharge)

Electric discharge(spark, arc)

Pantagraph, internalequipment in car, rectifier

Electric railway

Reflection From car body

Electric powerfacilities

Cassette transfer Magnetic field Cassette transfer equipment

Electric discharge Ignition circuitInternal combustionengines

Automobile

Others Dynamo, voltage regulator

Signal radiation* Broadcasting equipment,radar

Wirelesscommunicationfacilities

Large-powertransmissionequipment

Disturbance radiation High-frequency transmitter

Note: The signal marked with "*" is required in the relevant system, but becomes a disturnance signal forother system.

1.1.10

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Fig. 1-1 Installation Layout 1

Relevant instruments: (1) S-8840/S-8820(2) S-8640(3) S-8620’s with serial nos. 8343-xx onward

Power line (100 V AC, 50 A)

Evacuation duct

Dimensional unit: mm

Vacuum, air, N2 source

Inside diameter of duct: 104

Inside diameter of duct: 54Powersupply unit(H=1500)200 kg

Maintenanceservice area

f 65 caster(2 positions)

f 60 stopper(4 positions)

Control unit(H=1800)320 kg

Main columnunit (H=1650)1100 kg

Clean room

RP (Option)

Main unit base(6 positions)

f 60 stopper(3 positions)

f110 caster(2 positions)

f 110 caster(4 positions)

(Maintenance space formain section)

225 360

140

420

(H=520)30 kg

640

600

535

(100

0)

259 168200

345150

180 296

150

91

150

150

15058

(450)

125

122

80 310

570

1331

315

235

130

974

50 500

700 600

708

1890

624

540

400

74

144

287

582 295

134

719

512 309 260

1170

1.1 Installation Requirements

1 - 9

Fig. 1-2 Installation Layout 2

Relevant instrumente : (1) S-8620’s with serial no. 86xx-xx(2) S-8620’s with serial nos. up to 8342-xx

Dimensional unit: mm

Power line (100 V AC, 50 A)

Evacuation ductVacuum, air, N2 source

Inside diameter of duct: 104

Inside diameter of duct: 54Powersupply unit(H=1500)200 kg

RP (Option)

Maintenanceservice area

f 65 caster(2 positions) Clean room

f 60 stopper(4 positions)

Control unit(H=1800)320 kg

Main columnunit (H=1650)1100 kg

Main unit base(6 positions)

f 60 stopper(3 positions)

f 110 caster(2 positions)

f 110 caster(4 positions)

(Maintenance space formain section)

(H=520)30 kg

225 360

140

420

640

600

535

345

(100

0)

200150

180 296

150150

58

450

125

122

80 310

974

130

235

315

50 500

700 600

1331

570

150

150

287

582 295

134719

309 260512

1170

708

1810

624

540

400

74144

1.1.10

1 - 10

1.1.11 Power Capacitance

The power capacitance values of this instrument are shown below.

(1) At continuous turn-on time (only the evacuation system isactive during nighttime or stop of operation) • • • • • • • • • • • • • • • • • • • • • • •25 A

(2) At operation of instrument (the evacuation system, stage andcontrol circuit are active) • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 30 A

(3) At maintenance of instrument (the electron gun is baked orsubjected to heating/degassing treatment) • • • • • • • • • • • • • • • • • • • • • • • • • • • 45 A

(4) Power capacitance reserved for accessory device • • • • • • • • • • • • • • • • • • • •10 A

(5) Maximum power capacitance • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •45 A

* Under condition (3), it is not allowed to use electric power for stage, control circuit andaccessory device.

1.1.12 Evacuation Duct for Oil Rotary Pump (option)

WARNING

· Do not touch the metallic terminal section of the powersupply cable for the oil rotary pump, or you may receive anelectric shock.

· 100 V AC is supplied to the oil rotary pump. If you touchthe metallic terminal section of the power cable, it couldresult in death or serious injury.

· Do not touch the oil rotary pump itself nor its cover whilethe pump is operating; there is a danger you will be burned.

· The oil rotary pump becomes hot while it is operating.There is a danger of burns if you touch it.

1.1 Installation Requirements

1 - 11

As shown below, install the evacuation duct for rotary pump within the maintenance service area.

Fig. 1-3 Evacuation Duct Piping for Oil Rotary Pump (option)

Inside diameterof duct: 54 mm

Inside diameter of duct: 104 mm

Evacuation duct

To column unit

A B

RP-2

RP-1

520

360 640

340

160

222

250

1.1.12

1 - 12

1.2 Items to Be Prepared by User

Item Quantity Remarks

¡ Hexane (C6H14) 1 bottle Used for cleaning parts, special grade (500 mL)

¡ Vacuum pipes (tube diameter 6 mm,vacuum pressure P = 13 to 40 kPa)

1 set For evacuation of cassette-to-cassette loader

¡ N2 gas and air tubes

N2 gas (tube diameter 6 mm, pressure200 to 880 kPa)

Compressed air (tube diameter 6 mm,pressure 600 to 880 kPa)

1 set For loader chamber leak and valve drive

¡ Chamois leather cloth 1 set Used for cleaning devices and parts

¡ Evacuation duct (More than 6 m3 /minper pump)

1 set For two oil rotary pumps

¡ Chair 1 set For operator

¡ Lift (More than 1500 N (150 kgf)loadable at end)

1 set For maintenance of main unit

WARNING

· Inhalation of N2 gas could be dangerous.

· If tubing is performed with the N2 gas flowing, and a largeamount of the gas is inhaled, it could cause breathingdifficulty, and in the worst case, could be fatal.

· Before carrying out tubing for the N2 gas, make sure toclose the main valve for the N2 gas.

Air, N2 and vacuum tube connectors: KQS06-02S made by SMCJunflon or equivalent tubes should be used for the air, N2 and vacuum tubing, and the tuberesistance should be sufficient to withstand the pressure of the customer's facilities.When using tube joints (swage lock, VCR, etc.) other than specified by Hitachi, customer shouldprepave suitable tubing. (Connector size is Rc 1/4.)

Tube outer dia.6 mm

Rc 1/4

1.2 Items to Be Prepared by User

1 - 13

1.3 Power and Ground Wiring Connections

This instrument is designed to operate on 100 V input power voltage.

WARNING

· Do not touch the metallic terminal part of the power cable tothe instrument. There is a danger of electric shock.

· 100 V AC is supplied through the metallic terminal part of thepower cable. Touching this part could result in fatal orserious injury due to electric shock.

· Before connecting the instrument power cable or groundingwire to the power distribution board of the facility, make surethe output of the distribution board is turned OFF.

If other than 100 V input power must be used at installation, it is required to use the autotransformer (available optionally).

WARNING

· Do not touch the input or output metallic terminal sectionof the transformer. There is a danger of electric shock.

· 200 to 240 V AC is supplied through the input metallicterminal section and 90 to 115 V AC through the outputmetallic terminal section of the transformer. Touching these sections could result in fatal or seriousinjury due to electric shock.

· Before connecting the power cable or grounding wire ofthe facility to the transformer, make sure the powerdistribution board output of the facility is turned OFF.

1.3

1 - 14

[Reference]The tap voltage of the optional isolation transformer or auto transformer is shown in Fig. 1-4.

Fig. 1-4 Voltage Terminal of Auto Transformer (option)

Figure 1-5 shows the power cable connection from the distribution panel. The ground wireshould be grounded to a proper terminal (never connect the ground wire to a water pipe or thelike). (proper terminal is one with grounding resistance of less than 100 ohms)

(1) When auto transformer is not used

(2) When auto transformer is used

Fig. 1-5 Connection of Auto Transformer

INPUT

OUTPUT

90 V95 V100 V105 V110 V115 V

200 V220 V240 V

E3

1

2100 V AC

E

100 V AC

Power distribution panelPower supply unit

Power distribution panel

E3

1

2100 V AC

E

Power inputother than100 V AC

Power supply unit

E

G

1.3 Power and Ground Wiring Connections

1 - 15

Fig. 1-6 Wiring Diagram (S-8840/S-8640/S-8820/S-8620)

1.3

1 - 16

Fig. 1-7 Wiring Diagram (S-8840/S-8640,MFG No. 9101-01 onward)

1.3

2 - 1

2. FUNCTIONS

2.1 Appearance of Instrument System

Figure 2-1 shows the appearance of Model S-8000 series system.

Fig. 2-1 Appearance of S-8000 Series(Power supply unit and oil rotary pump unit are not shown here.)

Display unitMain column unit

2.1

2 - 2

2.2 Specifications

2.2.1 Specifications of S-8840/S-8640

(1) GeneralWafer size : S-8840 • • • • 8-inch or 6-inch

S-8640 • • • • 6-inch or 5-inchPrinciple of CD measurement : Cursor and line profile measurementCD measurement range : 0.1 to 10 µmCD measurementreproducibility : ±1% or 0.005 µm (3 sigma) (threshold method),

whichever largerThroughput : 26 wafers/hour (in continuous measurement),

1 point/chip, 5 chips/waferSecondary electron imageresolution : 5 nm (50 Å) (at accelerating voltage of 0.8 kV)

(with reference specimen dedicated for resolutionmeasurement)

Magnification : ´1000 to ´150,000 (SEM image)About ´110 (optical microscope image)

(2) Specimen StageMovement range : X and Y • • • • 0 to 200 mmStage drive : Pulse motorControl and speed : Computer-controlled, max. speed 50 mm/s

(3) Wafer LoaderWafer transfer from cassetteto loader chamber : Auto transfer via cassette-to-cassette auto loaderWafer transfer fromloader chamber to stage : Auto evacuation and auto loading

(4) Cassette-to-Cassette Auto LoaderPrinciple of loading : Loading via arm type robot for random access using two

cassettesChucking : Vacuum chucking on back of waferOrientation flat setting : Non-contact auto detection via optical sensor

2.2 Specifications

2 - 3

(5) Electron OpticsElectron gun : Schottky emission type (having high brightness and long

service life)Accelerating voltage : 500 to 1300 V (variable in 10 V steps)Lens system : Electromagnetic condenser lens system, FCM objective

lensSecondary electron detection : 2-stage detection systemObjective lens aperture : Heating type movable aperture (4 openings selectable

outside column), fine adjustment possibleScanning coil : 2-stage deflectionStigmator coil : 8-pole electromagnetic type (X, Y)Probe current monitoring : Faraday cup incorporated, with automatic measurement

functionOptical microscope : 1.2-mm-square visual field, monochrome image

(6) Control and Display SystemViewing control CRT : EWS (GUI) 20-inch monitor, integral processing image

display, interactive computer operation, wafer mapdisplay, measured value indication, stage coordinateindication, etc.

Scanning modes : TV scan, raster rotation, auto brightness/contrast controlPhotographing : Photographic recording unit, effective visual field 80 5

80 mm (option)Safety device : Equipped with emergency cut-off switch

(7) CD Measurement Data Processing System (1 GB hard disk for system program *)File storage : 3.5-inch floppy disk drive, 3.5-inch magneto-optic disk

drive, with storage function for various parameter filesData processing : Average value, standard deviation, maximum/minimum

valuesPrintout : 80-character thermal printer

* Hard disk capacity varies with instrument serial no.

(8) Vacuum SystemPrinciple of evacuation : Full automatic dry-clean evacuationVacuum pumping : Ion pump (3 units), turbo molecular pump (2 units),

rotary pump (option)(with foreline trap) (2 units)Safety device : Equipped with power fail/vacuum level safety devices

(9) DimensionsMain column unit : 1170W 5 1890D 5 1650H mm, 1100 kgDisplay unit : 600W 5 1331D 5 1800H mm, 320 kgPower supply unit : 535W 5 600D 5 1500H mm, 200 kgRotary pump (option) : 360W 5 640D 5 520H mm, 30 kg/unit

2.2.1

2 - 4

(10) Standard System CompositionMain column unit • • • • • • • • • • • • • • • • • • • • • 1Display unit • • • • • • • • • • • • • • • • • • • • • • • • • 1Power supply unit • • • • • • • • • • • • • • • • • • • • •1Photographing unit (option) • • • • • • • • • • • • • •1Rotary pump (option) • • • • • • • • • • • • • • • • • • 2Standard tools • • • • • • • • • • • • • • • • • • • • • • •1 setSpares and consumables • • • • • • • • • • • • • • •1 setInstruction manual • • • • • • • • • • • • • • • • • • • •1

2.2.2 Specifications of S-8820/S-8620

(1) GeneralWafer size : S-8820 • • • 8-inch or 6-inch

S-8620 • • • 6-inch or 5-inchPrinciple of CD measurement : Cursor and line profile measurementCD measurement range : 0.1 to 10 µmCD measurementreproducibility : ±1% or 0.005 µm (3 sigma) (threshold method),

whichever largerThroughput : 20 wafers/hour (in continuous measurement),

1 point/chip, 5 chips/waferSecondary electron imageresolution : 5 nm (50 Å) (at accelerating voltage of 0.8 kV)

(with reference specimen dedicated for resolutionmeasurement)

Magnification : ´1000 to ´150,000 (SEM image)About ´110 (optical microscope image)

(2) Specimen StageMovement range : X and Y ; 0 to 200 mm*Stage drive : Pulse motorControl and speed : Computer-controlled operation, max. speed 50 mm/s

* Hard disk capacity varies with instrument serial no.

(3) Wafer LoaderWafer transfer from cassetteto loader chamber : Auto transfer via cassette-to-cassette auto loaderWafer transfer from loaderchamber to stage : Auto evacuation and auto loading

2.2 Specifications

2 - 5

(4) Cassette-to-Cassette Auto LoaderPrinciple of loading : Loading via arm type robot for random access using two

cassettesChucking : Vacuum chucking on back of waferOrientation flat setting : Non-contact auto detection via optical sensor

(5) Electron OpticsElectron gun : Schottky emission type (having high brightness and long

service life)Accelerating voltage : 700 to 1300 V (variable in 10 V steps)Lens system : Electromagnetic condenser lens system, FCM objective

lensSecondary electron detection : 1-stage detection systemObjective lens aperture : Heating type movable aperture (4 openings selectable

outside column), fine adjustment possibleScanning coil : 2-stage deflectionStigmator coil : 8-pole electromagnetic type (X, Y)Probe current monitoring : Faraday cup incorporated, with automatic measurement

functionOptical microscope : 1.2-mm-square visual field, monochrome image

(6) Control and Display SystemViewing control CRT : EWS (GUI) 20-inch monitor, integral processing image

display, interactive computer operation, wafer mapdisplay, measured value indication, stage coordinateindication, etc.

Scanning modes : TV scan, raster rotation, auto brightness/contrast controlPhotographing : Photographic recording unit, effective visual field 80 5

80 mm (option)Safety device : Equipped with emergency shut-off switch

(7) CD Measurement Data Processing System (1 GB hard disk for system program *)File storage : 3.5 inch floppy disk drive, 3.5 inch magneto-optic disk

drive, with storage function for various parameter filesData processing : Average value, standard deviation, maximum/minimum

valuesPrintout : 80-character thermal printer

* Hard disk capacity varies with instrument serial no.

(8) Vacuum SystemPrinciple of evacuation : Full-automatic dry and clean evacuationVacuum pumping : Ion pump (3 units), turbo molecular pump (2 units), rotary

pump (option)(with foreline trap) (2 units)Safety device : Equipped with power fail/vacuum level safety devices

2.2.2

2 - 6

(9) DimensionsMain column unit : 1170W 5 1890D 5 1650H mm, 1100 kg

(S-8620 with serial nos. 8343-xx onward and S-8820)1170W 5 1810D 5 1650H mm, 1000 kg(S-8620 with serial no. 86xx-xx and nos. up to 8342-xx)

Display unit : 600W 5 1331D 5 1800H mm, 320 kgPower supply unit : 535W 5 600D 5 1500H mm, 200 kgRotary pump(option) : 360W 5 640D 5 520H mm, 30 kg/unit

(10) Standard System CompositionMain column unit • • • • • • • • • • • • • • • • • • • • • 1Display unit • • • • • • • • • • • • • • • • • • • • • • • • • 1Power supply unit• • • • • • • • • • • • • • • • • • • • • 1Photographing unit (option)• • • • • • • • • • • • • •1Rotary pump (option) • • • • • • • • • • • • • • • • • • 2Standard tools • • • • • • • • • • • • • • • • • • • • • • • 1 setSpares and consumables • • • • • • • • • • • • • • • 1 setInstruction manual • • • • • • • • • • • • • • • • • • • • 1

2.3 Main Column Units

2 - 7

2.3 Main Column Units

WARNING

· Do not touch components inside the instrument. There is adanger of electric shock.

· There are circuits using 6 kV DC and 100 V AC inside thisunit. Touching live or exposed parts of the circuits couldresult fatal or serious injury due to electric shock.

· Before detaching the cover of this unit, be sure to carry outthe workstation shutdown sequence and turn OFF the powerof the electron gun HV power supply.

2.3.1 General

Figure 2-2 shows the appearance of the main column unit of S-8000 series. The microscopecolumn (including the electron gun, lens system and secondary electron detector) is enclosed byexternal covers.

Fig. 2-2 Appearance of S-8000 Series Main Column Unit

Stage/evacuation control (manual) panel

Column front cover

Objective movable aperture

Specimen chamber(inside)

Auto loader

Load lock chamberVacuum system (inside)

2.3.1

2 - 8

2.3.2 Evacuation System

Figure 2-3 shows the evacuation system arrangement for S-8840, S-8640, S-8820 and S-8620.

IP1, 2, 3 : Ion pumpsRP1, 2 : Rotary pumpsTMP1, 2 : Turbo molecular pumpsPi1, 2 : Pirani gaugesPe1, 2 : Penning gaugesVS : Atmospheric pressure sensorLV1 ~ LV4 : Leak valvesAV1 ~ AV8 : Vacuum valvesF : FilterAV1 : Electron gun-specimen chamber airlock valveAV2 : Specimen chamber-loader chamber airlock valve

Fig. 2-3 Evacuation System Arrangement (S-8840, S-8640, S-8820, S-8620)

N2

LV2 F

IP1

MV1

IP2

IP3

MV2

MV3

AV1

LV1Pi3

XC

LD

VS

AV2 SCLCAV3Pe2

Pi2

AV5AV6

LV4

AV4

Pe1Pi1 AV8

LV3

AV7

RP1TMP2RP2

TMP1

2.3 Main Column Units

2 - 9

2.3.3 Evacuation Control (Manual) Panel

(1) VALVE CONTROL Section

CAUTIONThe VALVE CONTROL section is provided with switches exclusively for use by the serviceengineers. The user should never tamper with these switches, or else a serious troublemight occur in the system.

AUTO-MANUAL switch : Used for selection between the full AUTO mode andMANUAL mode of evacuation system operation. (Forexclusive use by service personnel)

VALVE AV1 to AV8,LV1 to 2 switches : Used for opening/closing each valve manually.

(To open each valve, turn the switch to UP position; toclose it, turn the switch to DOWN position.)The middle-point dot (•) indicates the stop state.(For exclusive use by service personnel)The lamp located above each switch lights up when thevalve is opened.

(2) ION PUMP SectionRANGE (Pa) switch : Used for selecting a vacuum level range of the ion pump.

Pa = Pascal1 Pa = 7.5 5 10-3 Torr1 Torr = 133 Pa

ION PUMP meter : Indicates a vacuum level of the ion pump (IP).RESET switch : Used to reset and start the ion pump (IP1, IP2, IP3).SELECT switch : Used for selecting a reading of the vacuum gauge (meter) of

ion pump.

(3) PIRANI & PENNING GAUGE SectionPIRANI &PENNING GAUGE meter : Indicates a reading of the Pirani/Penning vacuum gauge.SELECT switch : Used for meter reading selection.

2.3.3

2 - 10

(4) TMP CONTROL SectionSTART switch : Used to start up the TMP motor. Pressing this switch turns

on the pump.STOP switch : Used to stop the TMP motor.FAIL lamp : Lights up if the TMP operation becomes abnormal.ACC lamp : Lights up during an acceleration period until the TMP motor

reaches its normal rotating speed after the START switch ispressed.

NORM lamp : Lights up when the TMP reaches its normal rotating speed(rated speed level).

(5) ION PUMP BACKUP Section(Available in case the optional ion pump backup power supply is equipped)BATTERY OPERATIONswitch : During operation of this instrument, keep this switch to ON

position always.When the main power supply and this switch are turned off,the output voltage for pump goes off.

AC ON lamp : Indicates that the main (AC) power is connected.HV ON lamp : Indicates that the output voltage for pump is turned on.

When this lamp remains lit even after the main (AC) power isshut off, it indicates that a high voltage is applied to thepump.Before removing the ion pump voltage connector or air-leaking the electron gun chamber, turn off the BATTERYOPERATION switch and make sure that this lamp isextinguished.

Meter : Indicates an item chosen by the SELECT switch mentionedbelow.

SELECT switch : Used for meter reading selection. 5100 mA 510 mA : Indicates an output current of the pump power supply.

(When the main power supply is turned on, the reading iszero.)

kV : Indicates an output voltage of the pump power supply.4.5 kV is applied under normal condition.

V/BATTERY : Indicates a battery voltage. When a voltage of less than12 V is indicated, the charged amount of battery voltage isinsufficient.

2.3 Main Column Units

2 - 11

V/CHARGE : When this switch position is selected, a battery voltage isindicated on the meter and the quick charging operation isperformed.If the charged amount of battery voltage is insufficient (lessthan 12 V on V/BATTERY range) or the backup function isactivated due to power failure, turn the SELECT switch toany other position once and then return it to this position.(Quick charging is performed for approx. 10 hours. Aftercompletion of quick charging, the normal charge condition isset up.)

APS lamp : Turns on when the valve drive air pressure is higher than thespecified level.

VS lamp : Turns on when the specimen exchange chamber hasatmospheric pressure.

APT HEAT lamp : Turns on when the objective aperture is heated.

(6) Stage/Loader Control (Manual) Section

CAUTION

This control panel is intended exclusively for use by the service engineers. The user shouldnot tamper with this panel.

AUTO-MANUAL switch : Used for selection between the CPU-controlled automaticoperation of stage/loader and the manual operation.(For exclusive use by service personnel)

SPEED select switch : Selects a stage travel speed; HIGH, MED (IUM), or SLOW.X(+), X(-) switch : Selects the positive (+) or negative (-) direction of X

movement of the specimen stage.Y(+), Y(-) switch : Selects the positive (+) or negative (-) direction of Y

movement of the specimen stage.L(+) switch : Transfers the wafer holder from the load lock chamber to the

specimen stage. (Functional only in the MANUAL mode)L(-) switch : Transfers the wafer holder from the specimen stage to the

loader chamber.(Functional only in the MANUAL mode)

CHUCK switch : Used to chuck the wafer holder when unloading it.(Functional only in the MANUAL mode)

UNCHUCK switch : Used to unchuck the wafer holder when loading it.(Functional only in the MANUAL mode)

ARM switch : Used for wafer exchange in the load lock chamber betweenthe wafer holder and the station.

2.3.3

2 - 12

PALETTE switch : Moves up/down the center palette at the station.STAGE CONTROLXY : Indicates X-Y coordinates of the specimen stage.

(Unit: µm)X LIMIT (+) (-) lamp : Lights up if the positive (+) or negative (-) direction limit of X

stage movement is exceeded. This lamp does not turn onunder normal operation.(Flashing of this lamp indicates an overrun state.)

Y LIMIT (+) (-) lamp : Lights up if the positive (+) or negative (-) direction limit of Ystage movement is exceeded. This lamp does not turn onunder normal operation.(Flashing of this lamp indicates an overrun state.)

LOADER LIMIT (+) lamp : Lights up if the loader moves beyond the topmost positionon stage side. This lamp does not turn on under normaloperation.(Flashing of this lamp indicates an overrun state.)

LOADER LIMIT (-) lamp : Lights up if the loader moves beyond the return position inthe load lock chamber. This lamp does not turn on undernormal operation.(Flashing of this lamp indicates an overrun state.)

CHUCK lamp : Indicates that the loader is ready to chuck the wafer holder.

HOLDER ON STAGElamp : Indicates that the wafer holder is placed on the stage of

specimen chamber.HOLDER ON LOADERlamp : Indicates that the wafer holder is set at the home position of

load lock chamber.WAFER ON STATIONlamp : Indicates that the wafer is set on the station in the load lock

chamber.WAFER ON HOLDERlamp : Indicates that the wafer is set on the wafer holder in the load

lock chamber.LOAD/UNLOADPOSITION lamp : Indicates that the stage is located at the LOAD/UNLOAD

position.WAFER STATION UPlamp : Indicates that the wafer station is in the specimen exchange

chamber.WAFER STATIONDOWN lamp : Indicates that the wafer station is in the load lock chamber.

2.3 Main Column Units

2 - 13

TRANSFER ARMCHUCK A lamp : Indicates that a voltage is applied to the vacuum-chuck arm

A.TRANSFER ARMCHUCK B lamp : Indicates that a voltage is applied to the vacuum-chuck arm

B.

2.3.3

2 - 14

Fig. 2-4 Stage/Evacuation Control (Manual) Panel(S-8840/S-8640/S-8820/S-8620)

2.3.3

STAGE CONTROL

LOAD/UNLOAD POSITON

WAFER STATION UP

WAFER STATION DOWN

TRANSFER ARM CHUCK A

MANUAL

X LIMIT +

Y LIMIT -

Y LIMIT +

X LIMIT -

LOADER LIMIT +

LOADER LIMIT -

CHUCK

HOLDER ON STAGE

HOLDER ON LOADER

WAFER ON STATION

WAFER ON HOLDER

X

Y

SPEED CHUCK ARM PALETTEX+ Y+ L+

X- Y- L- UNCHUCKAUTO

START NORM FAIL START NORM FAIL

START STOP START STOP

TMP 1 TMP 2

AV8 AV9 AV10 AV11 LD LV1 LV2

AV1 AV2 AV3 AV4 AV5 AV6 AV7VALVECONTROL

MANUAL

AUTO

OPENCLOSE

OPENCLOSE

OFFBATTERY

OPERATION

AC ON HV ON

ION PUMPBACK UP

ON

SELECT

x10µA

x100µA

kV V/BATTERY

V/CHARGE

SELECT

Pi2

Pi1

Pi3Pe1

Pe2

SELECT

IP1IP2

IP3

IP1 IP2 IP3

RANGE

10-4

10-3

10-510-6

10-7

PIRANI & PENNING GAUGE

ION PUMP

APS

VS

APT HEAT

TRANSFER ARM CHUCK B

Stage/loader control (manual) section Evacuation control (Manual) section

2 - 15

2.3.4 Auto Loader System

(1) Outline of Auto LoaderThis auto loader is of a cassette-to-cassette type which loads/unloads wafers automatically.Up to two wafer cassettes can be set on the auto loader.

Fig. 2-5 Auto Loader on S-8000 Series

(2) Major Specifications of Auto LoaderWafer size : On Model S-8840/S-8820 • • • •8 or 6 inches in diameter

(conforming to the SEMI and JEIDA standards)On Model S-8640/S-8620 • • • •6 or 5 inches in diameter(conforming to the SEMI or JEIDA standards)

Principle : Random access loading with two cassettesChucking : Vacuum-chucking on back side of waferOrientation flat setting : Automatic setting

Wafer cassette

Auto loader

Load lock chamber

2.3.4

2 - 16

(3) Functions of Auto Loader

Fig. 2-6-1 Mechanisms of Auto Loader

Cassette mounting base : Mounts the wafer cassette.Cassette positioning guide : Used for positioning the wafer cassette for correct

mounting.Side-A cassette operationindicator lamp : This lamp indicates the cassette operation state on side A

as described below.(One of the following lamps lights up or flashes.)

MOUNTED : Lights up when the wafer cassette is set.WAITING : Lights up when the auto loader is waiting for processing (after the

instruction for processing is given).PROCESSING : Flashes during wafer processing.FINISHED : Lights up on completion of wafer processing.

Turns off when the cassette is removed.

'Side-A cassette' means the wafer cassette located near the loader chamber.

Wafer transfer arm

Cassette positioning guide

Orientation flat sensor

Cassette positioning guide

Cassette mounting base

Side-B cassette operationindicator lamp

Cassette mounting base

Side-A cassette operationindicator lamp

Wafer transfer (WT)

2.3 Main Column Units

2 - 17

Side-B cassette operationindicator lamp : Functionally same as the side-A cassette operation

indicator lamp.'Side-B cassette' means the wafer cassette located fartherfrom the loader chamber.

Orientation flat sensor : Detects the orientation flat and centering position of wafer.The position of sensor varies depending on the wafer size.

Wafer transfer arm : Transfers the wafer into or out of the specimen exchangechamber.a) At Loading

The wafer is taken out of the side-A/B wafer cassette. ¯

The wafer is transferred to the orientation flat sensorand then transferred out of it.

¯The wafer is transferred to the station holder in thespecimen exchange chamber.

b) At UnloadingThe wafer is transferred out of the station holder in thespecimen exchange chamber

¯The wafer is stored into the side-A/B wafer cassette.

2.3.4

2 - 18

(4) Mounting of Wafer Cassette

CAUTION

Beware of injury

· There is a possibility of injury while the wafer transfermechanism is operating.

· Do not touch inside the cassette loader with the powerturned on.

Place the wafer cassette onto the cassette mounting base. At this step, make sure thatthe cassette positioning plates are secured positively on the cassette mounting base.If the wafer cassette is not mounted properly, pressing the START switch causes an errormessage to appear on the CRT monitor to indicate the inoperable condition.

Fig. 2-6-2 Mounting of Wafer Cassette

Cassette

Cassette positioning plate

Cassette mounting base

2.3 Main Column Units

2 - 19

2.3.5 Objective Movable Aperture Control

Fig. 2-7 Objective Movable Aperture Control

APERTURE SELECT knob : Used for selecting one of four apertures.(Diameter of opening: 0.002 mm ´ 4)

FINE ADJUST (X) knob : Used for fine adjustment in the X-axial direction (perpendicular toIN/OUT direction).

FINE ADJUST (Y) knob : Used for fine adjustment in the Y-axial direction (IN/OUT direction).

FINE ADJUST (X) knob

FINE ADJUST (Y) knob

APERTURE SELECT knob

2.3.5

2 - 20

2.4 Display Unit

2.4.1 Appearance of Display Unit

Figure 2-8 shows the appearance of the display unit.

Fig. 2-8 Appearance of Display Unit

2.4.2 Functions

(1) Power Supply Switch Panel Figure 2-9 shows the layout of the power supply switch panel.

EMERGENCY STOP

ON ONON ON

OFF OFF OFF OFF

EVACESTAGE I.P/HVSEM

Fig. 2-9 Layout of Power Supply Switch Panel

2.4 Display Unit

EMERGENCY STOP switch

IP/HV switch

EVAC switchSTAGE switch

SEM switch

Electron gun high voltage power supply

Power supply switch panel

Display monitor

(Workstation main unit) Floppy disk drive

Keyboard, mouse

Printer

Magneto-optical disk drive

Operation table/panel

2 - 21

EMERGENCY STOPswitch : Pressing this switch shuts off all the power supply circuits other

than that of the workstation main unit.< In case the backup power supply is mounted >Even after this switch is pressed, the electron gun evacuation ionpump and the electron gun high voltage power supply remainactive for a specified period of time. Take the followingprocedure for stopping the buzzer.1) Make sure there is no problem related to safety.2) Remove the rear cover from the power supply rack.3) Turn OFF the power switch of the backup power supply for

workstation, located on the 2nd shelf from the top in the powersupply rack.

Before using the instrument, turn ON the power switch of thebackup power supply for workstation, and then start up theinstrument.

IP/HV switch : Serves as the main power switch for the ion pump power supplyand the electron gun high voltage power supply.

EVAC switch : Turns on/off power to the evacuation system.STAGE switch : Turns on/off power to the stage/loader system.SEM switch : Turns on/off power to the display unit.

Four switchesdescribed above• • • Power is connected by pressing ON, and it is disconnected by pressing

OFF.Under normal condition, power to the display unit should be turnedon/off through the workstation. Use the above SEM switch to shut offpower only when abnormality (e.g. disabled workstation operation)takes place.For power supply to the ion pump, it is also required to make setting onthe evacuation control panel.Pressing the EMERGENCY STOP switch cuts off the power supply.But for the workstation, power is cut off after completing the shutdownprocess via the backup power supply.If the IP/HV ON lamp does not light up even when the switch is pressedor goes off when it is released, check whether the main switch onpower supply rack or the relevant circuit breaker is turned on or not.

2.4.2

2 - 22

(2) Electron Gun High Voltage Power SupplyFigure 2-10 shows the layout of the electron gun high voltage power supply panel. Do nottouch this panel unless it is necessary to shut off the electron gun high voltage power due toabnormality.

ho urs

M A X If

P O W E R

ST A R T U P

ST A R T D O W N

Ie I f G N D

D O W N U P

I f

V s

V 1

V 2

V 0

Fig. 2-10 Layout of Electron Gun High Voltage Power Supply

Under normal condition, set the POWER switch to ON position always. The high voltagepower to electron gun should be turned on/off through the workstation.Turn off the POWER switch only when operation through the workstation is disabled andthe high voltage power must be shut off.

NOTICE: This is because the probe current will become unstable.

Each press of the display select switch presents each data in succession on the displaywindow. The display select lamp indicates what item is being displayed.The following items can presented on the display window.

If : Heating current to Schottky emitterVs : Suppressor voltageV1 : Emission extracting voltageV2 : Intermediate electrode voltageV0 : Accelerating voltage

(When a retarding voltage is applied, this accelerating voltage level differs from thatindicated in image operation.)

Ie : Emission current

Under normal condition, select 'Ie' (emission current) for display.

2.4 Display Unit

Heating current settingdial

HV READY lamp

HV ON lamp

Display window

Display select lamp

Display select switch

Control switchPower supply indicatorlamp

POWER switch

2 - 23

(3) Display MonitorThe display monitor is equipped for workstation operation. It can present all theinformation necessary for operation (including images).

(4) Keyboard and MouseFor ordinary operation, the screens on the display monitor can be controlled using themouse. To enter numeric values and file names, use the keyboard.For details of the operational procedures, refer to 'OPERATION SECTION' of InstructionManual.

(5) Control PanelUse the control panel for image focus adjustment or other control operations that are ratherdifficult to perform with the mouse. Fig. 2-11 shows the layout of the control panel.

SSSS TTTT IIII GGGG MMMM AAAA FFFF OOOO CCCC UUUU SSSS

BBBBEEEEAAAAM M M M SSSSTTTT AAAAGGGG E E E E OOOOFFFF FFFF

Fig. 2-11 Layout of Control Panel

FOCUS knob : Used for manual focus adjustment of SEM image.STIGMA knob : Used for manual astigmatism correction of SEM image.BEAM switch : When this switch is pressed, its lamp (located above) lights up.

In this state, the visual field of image (electron beam) can be shiftedusing the trackball.The visual field shift range is limited to 30 µm.

STAGE switch : When this switch is pressed, its lamp (located above) lights up.In this state, the specimen stage can be moved using the trackball.

OFF switch : Pressing this switch turns off both the BEAM and STAGE lamps.In this state, the trackball is not effective.

The above functions are also available through use of the workstation.

STIGMA knob

FOCUS knob

OFF switch

STAGE switch

BEAM switch

Trackball

2.4.2

2 - 24

(6) Printer This printer is used for measurement data output. Fig. 2-12 shows the external view of theprinter.

Fig. 2-12 External View of Printer

FEED switch : Used for paper feed.RESET switch : If the ERROR lamp lights up, press this switch with the tip of

mechanical pencil or the like.ON lamp : Indicates power connection to the printer. When this lamp is lit,

power is supplied to the printer normally.PAPER END lamp : Lights up when paper runs out.ERROR lamp : Lights up if any error is encountered with the printer.Lever : To insert paper, turn this lever up. For printing, turn it down.

Lever

RESET switch

FEED switch

ON lampPAPER END lamp

ERROR lampPaper stocker cover

2.4 Display Unit

2 - 25

How to Load Printing Paper

WARNING

· Do not touch the paper cutter, or you may cut your fingers.The cutter has a sharp blade.

· On occurrence of a paper jam, remove the jammed part ofpaper using tweezers, not your bare hands.

Open the cover of paper stocker, turn the lever up, and take out the core shaft.Insert the core shaft into a new roll of paper, set it on the paper holder. Then, run the topof paper roll through the printing section as shown below. (It is advisable to fold the top ofpaper into a triangular form so that paper can be run through the printing section easily.)When the top of paper appears from the outlet, turn the lever down. Then, by pressing theFEED switch, make sure that paper is fed normally.

Structure of Printer

How to Cut Printing PaperThe cutter is provided along the top of the paper outlet. For cutting paper, pull it obliquelyupward.

How to Print OutFor the data printout procedure, refer to 'OPERATION SECTION' of Instruction Manual.

(7) Magneto-optical Disk Drive The 3.5-inch magneto-optical disk drive is equipped in the display unit. For the operationalprocedure, refer to 'OPERATION SECTION' of Instruction Manual.

Lever

Paper cutter

Paper inlet

Stocker cover

Printing section

2.4.2

2 - 26

2.5 Power Supply Unit

WARNING

· Do not touch components inside this unit, or you mayreceive an electric shock.

· This unit supplies 5 kV DC and 100 V AC to the display unitand column unit. Touching live or exposed parts insidethis unit may result in fatal or serious injury due to electricshock.

· Before detaching the cover of this unit, be sure to turn OFF allthe power to the instrument.

2.5 Power Supply Unit

2 - 27

2.5.1 General

The power supply unit is designed for supplying power to each circuit of this system. Fig. 2-13shows the external view of the power supply unit.

E L E C T R IC IT Y O N P OW E R O N E M E R GE N C Y S T O P

Fig. 2-13 External View of Power Supply Unit

ELECTRICITY ON lamp : Lights up when commercial power is fed to the input circuit of thepower supply unit.

POWER ON lamp : Lights up when the MAIN circuit breaker of the power supply unit isturned on.

ELECTRICITY ON lamp

POWER ON lamp

EMERGENCY STOP switch

< Ion pump power supply section >

IP1 switch and lamp

IP2 switch and lampIP3 switch and lamp

INNER BAKE switch

OUTER BAKE switch

OUTER BAKE circuit breaker

< Baking timer >

EVAC POWER circuit breaker

RP1 circuit breakerIP/FL POWER circuit

STAGE POWER circuit breakerDISPLAY POWER circuit breakerRP2 POWER circuit breaker

MAIN circuit breakerPUSH switch

2.5.1

2 - 28

EMERGENCY STOPswitch : Used to shut off the entire power to the instrument system (except

the workstation unit).Note: Where the backup power supply circuit for the electron

gun evacuation pump/electron gun high voltage powersupply is provided, power is supplied continuously for apredetermined period of time even if the EMERGENCYSTOP switch is pressed.

Take the following procedure for stopping the buzzer.1) Make sure there is no problem related to safety.2) Remove the rear cover from the power supply rack.3) Turn OFF the power switch of the backup power supply for

workstation, located on the 2nd shelf from the top in the powersupply rack.

Before using the instrument, turn ON the power switch of thebackup power supply for workstation, and then start up theinstrument.

< Ion Pump Power Supply Section >IP1 switch and lampIP2 switch and lampIP3 switch and lamp : These power switches are equipped for three ion pumps.

Each power lamp lights up when the relevant ion pump is poweredon.Even if the power switch is turned on, the power lamp does not lightup after the protective circuit is activated due to overload or othercauses.In this case, it is required to press the ion pump reset switch locatedon the evacuation control panel (on the front of main column unit).The evacuation control panel is also provided with the ion pumppower lamp. In ordinary operation, use it to check power-oncondition of the ion pump.

2.5 Power Supply Unit

2 - 29

INNER BAKE switchOUTER BAKE switchOUTER BAKE circuit breakerBaking timer : These switches and timer are used for baking the electron gun

(degassing operation by heating).The baking of electron gun should be conducted by servicepersonnel. So, keep the above three switches at OFFpositions. The user should not turn on these switches.On the timer, all the knobs should be set at the extremecounterclockwise positions.Even if these switches are turned on, heating is not carried outto ensure safety (unless the high voltage cable is removedfrom the electron gun and set in the specified cablecompartment).

EVAC POWERcircuit breaker : Serves as the main circuit breaker for the evacuation system.RP1 POWER circuit breakerRP2 POWER circuit breaker : Serves as the circuit breakers for the rotary pumps equipped

behind the evacuation power supply.Equipped to protect the rotary pumps against overcurrent.Power is not supplied to the evacuation system unless boththe circuit breakers are turned on.

DISPLAY POWERcircuit breaker : Serves as the main circuit breaker for the display unit.STAGE POWERcircuit breaker : Serves as the main circuit breaker for the specimen stage

unit.IP/FL POWER circuit breaker : Serves as the main circuit breaker for the ion pump power

supply (for electron gun evacuation) and the electron gun highvoltage power supply.

MAIN circuit breakerPUSH switch : Used for turning on/off power to the entire power supply unit.

The electric leakage breaker function is provided.For power connection, turn on the MAIN circuit breaker whileholding down the PUSH switch.The MAIN circuit breaker shuts off in the following cases:

(1) On occurrence of electric leakage(2) At power recovery after power failure(3) When the EMERGENCY STOP switch is pressed

After one of the above events takes place, the MAIN breakerlever is set at the middle position. To turn power on again,press the lever to DOWN position once. Then, throw thelever to UP position while holding down the PUSH switch.

2.5.1

3 - 1

3. PRINCIPLE OF MICROSCOPE INSTRUMENT

3.1 Schottky Emission (SE) Electron Source

The Schottky emission electron source, proposed by Dr. N.W. Swanson, et al. in the 1980s, hasoutstandingly excellent stability in its emission current. Owing to this superb feature, it hasfound extensive applications in a variety of electron beam devices.Briefly described below is the principle of SE electron source.A single crystal of tungsten (100) is formed into a probe having a curvature radius of approx.0.5 µm. Then, its tip is heated at about 1800 K in vacuum. Simultaneously, a monolayer ofZr-O is diffused on the tip so that 100 facets are provided on it. This results in the workfunction of tip being decreased from 4.5 eV to 2.7 eV, thereby making it easy to extract electronsin vacuum. Thus, the intensity of electron emission can be increased even at a low extractingvoltage.The stability of electron beam emitted in the above method largely depends on the vacuum levelin the atmosphere in which the tip is located. It is therefore required to provide ultra-highvacuum (10-7 Pa) in the atmosphere. Also, to ensure the stability of electron beam, the tip mustbe heated at all times. If the high voltage power supply for electron gun goes off due to apower failure, a period of approx. 30 minutes must be allowed before turning on electronemission again (including the diffusion time of Zr-O and the time until the temperature of tip issaturated up to about 1800 K).

3.1

3 - 2

3.2 Electron Optical System

3.2.1 Retarding Method

In this instrument, the retarding method is adopted to enhance resolution in a low acceleratingvoltage range.In the retarding method, a negative potential is applied to a wafer (specimen) for deceleratingelectron beam between the objective lens and the specimen. Fig. 3-1 shows the schematicdiagram of the retarding method. Until passing through the objective lens, the electron beam isaccelerated up to Vo. After going through the objective lens, the electron beam is deceleratedwith -VR applied to the specimen. Thus, the decelerated electron beam falls on the specimen.The accelerating voltage of electron beam incident on specimen (Vacc) is expressed as 'Vo-VR'.

This retarding method can make resolution far better than conventional approaches.In the present design, the retarding method mentioned above is used in a low acceleratingvoltage range of 700 to 800 V. In a high accelerating voltage range of 810 to 1300 V, the FCM(field control method)* is used. Changeover between the retarding method and the field controlmethod is performed automatically.

* The field control method has also been adopted in the conventional models. A positivepotential is applied to the FCM electrode shown in Fig. 3-1. In this method, the potential ofspecimen is set at zero (0).

3.2 Electron Optical System

3 - 3

3.2.2 Note on Retarding Method Operation

In the retarding method, since an electric field is applied between the objective lens andspecimen, astigmatism increases in a wafer circumferential area of 10 mm. So, avoidobservation/CD-measurement in this area. If it is required to carry out observation/CD-measurement in this area, set the accelerating voltage to 810 V or higher for FCM operation.

Fig. 3-1 Principle of Retarding Method

Although a negative potential is applied to a wafer in the retarding method as mentioned before,continuity is established through contact with the end face of wafer.If the surface or end of a wafer is covered with an insulating film, a potential cannot be appliednormally. And when the electron beam is irradiated, chargeup may occur to prevent normalimage observation. In such cases carry out the following for observation and CD measurement.

(1) Remove the insulating film from the wafer end.

(2) Set accelerating voltage to 810 V or higher and use the FCM mode for observation andmeasurement.

Electron beam accelerated to VoFCM electrode

Objective lens

Specimen holder (wafer)

Retarding (decelerating)electric field

Electron beamincident on specimen (Vacc) -VR

Vacc=VO-VR

3.2.2

3 - 4

3.3 Two-Stage Detection System (S-8840/S-8640)

In this system, an additional detector is provided to improve the detection efficiency forsecondary electrons emitted from the specimen. The purpose is to alleviate specimen damagedue to contamination by reducing the probe current at observation and CD measurement.And by adding a second detector, secondary electrons that could not be detected by the ordinarysystem using a single detector are now detectable, and new information can be obtained uponforming secondary electron images.Figure 3-2 gives an outline of the secondary electron detection method in the two-stagedetection system. Since the energy of secondary electrons accelerated by the retarding voltageis high, they cannot be detected directly. So, in the single-stage detection system, thesecondary electrons from the specimen strike the conversion electrodes, then the secondaryelectrons emitted from the electrodes are detected by the first detector. But since there aresome small holes (up to 4 mm dia.) in the conversion electrodes to let the primary electrons passthrough, some of the secondary electrons from the specimen also go upward through theseholes, and the S-8820/S-8620 did not allow detecting these signals.In the two-stage detection system, another conversion electrode and a second detector areadded above the first electrode and detector, whereby secondary electrons that wereundetectable in the single-stage system are now detectable. This improves the detectionefficiency and allows reducing the probe current.

Fig. 3-2 Outline of Secondary Electron Detection in Two-Stage Detection System

Conversion electrode

Seconddetector

Conversion electrode

Mixer SEM image signal

Firstdetector

Resist film, etc.

Wafer

Substrate

3.3 Two-Stage Detection System (S-8840/S-8640)

4 - 1

4. COMPUTER SYSTEM AND SOFTWARE

4.1 Computer System Configuration

Figure 4-1 shows the computer system configuration of CD-measurement SEM. A total of eightCPUs are provided to inter-work with one another through communication. These CPUs areconfigured so that they are controllable from the engineering workstation (EWS). Also, the colorCRT monitor of EWS can display SEM images or optical microscopical images. Briefed beloware the functions of CPU.

(1) EWSOffers an easy-to-use operating environment with the state-of-the-art GUI (graphical userinterface) technology.

(2) SEM ControllerDesigned to manage other control circuits in an integrated fashion. Also, this unit carriesout sequence processing for operation of electron optical mechanism, loading/unloading ofwafer, etc.

(3) Image Processing UnitUsed to search for an alignment mark or measurement pattern automatically.For automatic search, it is necessary to store alignment marks and measurement patternsin advance.

(4) HV Control UnitCarries out control of the electron gun.

(5) Evacuation Control UnitCarries out the evacuation/air-purge sequence for the specimen chamber and loaderchamber.

(6) Stage Control UnitControls wafer movement in the specimen stage/vacuum chamber.

(7) WT (Wafer Transport) Control UnitControls wafer movement in atmosphere.

(8) OFS Control UnitUsed for detection of orientation flat.

4.1

4 - 2

Fig. 4-1 Computer System Configuration

4.1 Computer System Configuration

External computer

Hard disk drive

Ethernet RS - 232C

Mouse

3.5 inch MO drive

Keyboard

Mini-printer

Operationcontrol panel

Color CRT1280 ´ 1024

Maintenanceservice panel

EWS PA - RISC GUI

Image Processing unit

Pattern recognition

SEM controller HVcontrol unit

Evacuationcontrol unit

Stage control unit WT control unitWafer transfer

OFS control unit

Maintenanceservice panel

Maintenanceservice panel

Maintenanceservice panel

5 - 1

5. FILES

In this system, a set of data such as CD-measurement result data is referred to as a file.Data contained in each file can be processed collectively. The files are classified into two majorcategories as shown below.

(1) System FilesControlled by the operating system of computer.The system files cannot be accessed directly by the user.

(2) User FilesCan be created or deleted by the user.

5.1 System Files

Table 5-1 shows the kinds and contents of system files.The system files are stored on the hard disk and loaded automatically at power-on. These filesare run transparently, i.e. it is not required for the user to pay attention to them for operation.

Table 5-1 System Files

Name Description Related Window

Automatic CD-measurementparameter file

Stores parameter data for CD-measurement Image Operation

CD-measurement valuecorrection file

Stores offset value data of CD measurement errordue to a change of magnification

Image Operation

User name record file Contains the user name, password, etc. Login

Stage coordinate storage file Used to hold up to 50 stage coordinate positions Stage Controller

Stage coordinate instrumentalerror correction file

Used to hold instrumental error data for stagecoordinates on particular instrument

Stage Controller

Optical microscope-electronmicroscope visual fieldcorrection file

Stores visual field correction value data for theoptical microscope and electron microscope

Stage Controller

Stage coordinate calibrationfile

Stores calibration value data for stagecoordinates

Instrument calibration file Stores instrument calibration data such asdeflection point of electron beam, up/down stepratio of image shift, etc.

5.1

5 - 2

5.2 User Files

Table 5-2 shows the kinds of contents of user files.

Table 5-2 User Files

Name Description Remarks

IDW file(Wafer information file)

Stores the on-wafer chip array and its size. Creation, revision, display• IDW Editor

IDP file(CD-measurement patternfile)

Stores the alignment pattern and CD-measurement pattern positions.

Creation, revision, display• IDP Editor

Recipe file Stores the RECIPE name, relevant IDWand IDP file names, CD-measurement slotdata, etc.

Revision, display• Recipe Editor

CD-measurement data file Stores the result data of CD-measurement.

Creation• Created automatically

in execution of recipe.Display• Work Sheet

Image file Stores images. Creation• Image Operation• Created automatically

in execution of recipeDisplay• Image File Manager• Work Sheet

5.2 User Files

5 - 3

5.2.1 Hierarchical File Structure

Figure 5-1 shows the hierarchical structure of user files. In this system, all the user files arecreated and saved hierarchically under each parent directory 'class'. This hierarchical filestructure is convenient for the user to classify files according to the kind of product or the processof fabrication.Each IDP file is created under the directory of relevant IDW file because of its nature.So, before creating an IDP file, be sure to prepare an IDW file corresponding to it.

class 1

Image 1

IDW 2

IDW 1

Recipe

IDP 2

IDP 1

class 2

Fig. 5-1 Hierarchical Structure of User Files

5.2.1

class 1

class 2

Recipe

IDW 1

IDW 2

IDP 1

IDP 2

CD-measurement data 1

Image 1

5 - 4

5.2.2 Handling of User Files

Described below is the general handling procedure for user files.

(1) IDW and IDP FilesAn IDW/IDP file can be created, modified, copied, deleted or renamed through use of eachFile Manager.For manual file loading, use the Manual Controller screen. When CD-measurement iscarried out with recipe specified, the relevant IDW and IDP files are loaded automatically.A name of IDW/IDP file can be given within 40 characters, including alphanumericcharacters, underbar (_) and hyphen (-).

(2) Recipe FileOne recipe file is provided for each 'class' directory. Each recipe file can contain up to 1000recipe data. Using the Recipe Manager, you can create, modify, copy, delete or renamerecipe data. Measurement using recipe data can be carried out through the RecipeController window. A recipe name may consist of up to 40 characters, includingalphanumeric characters, underbar (_) and hyphen (-).

(3) CD-measurement Data FileA CD-measurement data file is automatically generated in execution of the recipe thatinstructs saving of CD-measurement file. It is named in the format shown below."Date and time when CD-measurement is started _ Recipe name"Using the MSR File Manager, you can copy, delete or rename a CD-measurement data file.Also, on the MSR Eraser window (utility), you can specify automatic file deletion of CD-measurement data file. With setting of this function, the CD-measurement data file will bedeleted automatically when the specified number of days is reached.

(4) Image File (option)An image file can be created in the following two ways.(a) Storing from the Image Operation window

Click the Image... button of Image Operation, and the SEM Image Register screen willopen. Now enter a file name on this screen, and the image under observation will besaved.

(b) Execution of recipe for which image save is specifiedExecute the recipe for which image save is specified, and the images at alignment, atdetection of measurement pattern, and at CD measurement will be automatically saved.An image file can be displayed, copied, deleted, renamed or compressed through useof the Image File Manager. The images in the image file created automatically by theabove method (b) are displayed upon selecting Show MP Image or Show AP Image ofAction SW on the work sheet. Also, when the automatic deletion function of the CD-measurement data file is activated, the image file related to the deletedCD-measurement data file will also be automatically deleted.

5.2 User Files

6 - 1

6. COORDINATE SCHEMES

6.1 General

The following two coordinate schemes are provided in this system:

(1) Stage coordinate scheme(2) Wafer coordinate scheme

The stage coordinate scheme is used to indicate mechanical coordinates of the specimen stage.In the wafer coordinate scheme, the user can specify on-wafer coordinates after completingrelational calibration with the stage coordinate scheme.

6.2 Stage Coordinate Scheme

The specimen stage of this system is driven on X and Y axes. Table 6-1 shows the movablerange and minimum drive step of each axis.

Table 6-1 Movable Range and Minimum Drive Step

Axis Movable Range Minimum Drive Step

X (horizontal) 0 to 200 (150) mm* 0.25 mm

Y (vertical) 0 to 200 (150) mm* 0.25 mm

The X and Y stage coordinate positions are always indicated on the stage control panel.Each coordinate value is represented in dimensional unit of µm.With the orientation flat side facing down, the X axis corresponds to the horizontal direction andthe Y axis corresponds to the vertical direction.

The stage movable range on the X and Y axes is 0 to 200 mm, or else 0 to 150 mm *.Note, however, that the stage may not be movable in 20 µm region near the travel limits of 0 mmand 200 mm because of calibration of stage distortion.

* Stage movable range is 0 to 150 mm for S-8620 with serial no. 86xx-xx and serial nos. up to8342-xx.

6.1

6 - 2

6.3 Wafer Coordinate Scheme

For indicating wafer coordinate points, the following two kinds of values are specifiable.

(1) Chip number and on-chip coordinates(2) Wafer coordinates Before using the wafer coordinate scheme, it is necessary to predefine chip pitch and array usingthe IDW and IDP Editors. Also, alignment with the stage coordinate scheme is required asmentioned in 6.4.

6.3.1 Chip Number and On-Chip Coordinates

It is assumed that chips having identical configuration are arranged in a form of array. Each chipon wafer is indicated using a combination of chip number X in horizontal direction and chipnumber Y in vertical direction.Figure 6-1 shows the default setting of wafer coordinate scheme. The origin of wafer coordinatescheme is located at the lower left corner with the orientation flat or V-notch side facing down.A chip at this position is referred to the origin chip and it is indicated by chip number (0, 0).In most cases, the origin chip does not exist on wafer actually. It is also allowed to assign anyother chip as the origin chip using the IDW Editor.On each chip, the on-chip coordinate scheme is formed with the lower left corner of chip taken asthe origin point. In this scheme, the X axis corresponds to the horizontal direction, and the Yaxis corresponds to the vertical direction. Any pattern position on chip can be specified indimensional unit of µm on X and Y axes.

Fig. 6-1 Wafer Coordinate Scheme

6.3 Wafer Coordinate Scheme

ROWWafer

Chip (X, Y) = (4, 6)

Chip (X, Y) = (6, 4)

On-chip origin (0, 0)

On-chip coordinates

COLUMN

Origin (0, 0) Wafer coordinates

Origin chip(X, Y) = (0, 0)

Orientation flat (OF)(or V-notch)

6 - 3

6.3.2 Wafer Coordinates

In Fig. 6-1, the on-chip coordinate origin of the origin chip corresponds to the origin point of wafercoordinate scheme. Any wafer coordinate position can be represented by a combination ofX-direction and Y-direction values with respect to this origin point. The wafer coordinate X and Yvalues are related with the chip numbers and on-chip coordinates as shown below.

(Wafer coordinate X value) = (Chip number X) ´ (X direction pitch of chip) +

(On-chip coordinate X value)

(Wafer coordinate Y value) = (Chip number Y) ´ (Y direction pitch of chip) +

(On-chip coordinate Y value)

6.3.2

6 - 4

6.4 Wafer Alignment

For using the wafer coordinate scheme, it is required to establish positional relationship with thestage coordinate scheme. At each exchange of wafer, enter two relational points; the first andsecond alignment points. The two chips to be used for alignment are referred to as the first andsecond alignment chips. Demonstrated below is an example of manual alignment.For determining where alignment is to made, use the AP Chip Select screen shown in Fig. 6-2.This AP Chip Select screen can be called up from the IDP Editor. Before creating an IDP file,enter such parameters as chip array and chip size using the IDW editor.

Fig. 6-2 AP Chip Select

6.4 Wafer Alignment

Chip display area

Alignment chip countindication field

Chip number inputfield

6 - 5

The wafer alignment procedure is described below.

Fig. 6-3 Stage Coordinates and Wafer Coordinates

(1) Move the specimen stage to the first alignment position.Open the Stage Controller screen, and click ‘1st Move ’ button of Wafer Alignment.Then, the specimen stage will be moved to the approximate alignment position. If it isdifficult to find out the alignment pattern, select the optical microscopical (OM) image.Set the alignment pattern at the approximate center of screen.

(2) Enter the first alignment position.On the Stage Controller screen, click ‘1st Reg’ button of Wafer Alignment. The crosscursor will then appear. Bring this cursor to the alignment position, and then click OKbutton.

(3) Enter the second alignment position.In the same manner as for the first alignment position, click 2nd Move button and then Regbutton on the Stage Controller screen. When the second alignment position is determined,the wafer alignment procedure is completed.

6.4

1500 mm

1500 mm100 mm

1st alignment positionApprox. (19000, 69000) in stagecoordinate scheme

On-chip coordinate origin YROW

2nd alignment chip(6, 3)

COLUMN

(0, 0)

Wafercoordinateorigin

Wafer coordinates

1st alignment chip(0, 3)Stage coordinate origin

(0, 0)

Stage coordinates

X

100 mm

6 - 6

6.5 Visual Field Shift in Each Coordinate Scheme

The visual field can be shifted in the stage coordinate scheme or the wafer coordinate scheme.

Fig. 6-4 Stage Controller

(1) Stage Coordinate Control OperationAbsolute

Move : Movement according to the specified absolute position in the stage coordinatescheme.

RelativeMove : Movement according to the specified relative shift value in the stage

coordinate scheme.Special

ALP : Brings the stage to axial alignment specimen position.CLP : Brings the stage to the CD-measurement calibration specimen position.STP : Brings the stage to the astigmatism correction specimen position.

MemoryAction : Brings the stage to any memorized position.

6.5 Visual Field Shift in Each Coordinate Scheme

Map operation window start button

Stage coordinate display area

Memory drive area

Absolute value drive area

Relative value drive area

Wafer alignment area

Special position drive area

6 - 7

(2) Wafer Coordinate Control OperationOn the Stage Controller screen shown in Fig. 6-4, click Map Operation button. Then, theMap Operation screen will appear as shown in Fig. 6-5. Before using this screen, it isnecessary to load the IDW and IDP files into the system memory.On the Map Operation screen, the stage can be moved by specifying a combination of chipnumber and on-chip coordinate point. Also, it is allowed to reach a CD-measurement pointspecified in the IDP file.

Drive Mode Selection

Display Mode Selection

Display Area

Stage drive area

Map display area

Fig. 6-5 Map Operation

6.5

7 - 1

7. STARTUP AND SHUTDOWN OF INSTRUMENT

7.1 Startup

7.1.1 Usual Startup Procedure

This SEM’s evacuation system (ion pump and evacuation control mechanism) and electron gunHV power supply section are powered continuously under normal conditions. When initiatingroutine instrument operation (warm start), take the following startup procedure.When restarting the instrument after it has been stopped completely (cold start), refer to section7.1.2 or 7.1.3.

(1) Power-onTurn ON the STAGE and SEM power switches on the display.

Precaution at Power-on:

When STAGE and SEM power is turned on, do not operate keys until the message“Console Login:” appears. If Esc (Escape) or another key is pressed duringinstrument startup, the instrument start program will be interrupted and the instrumentmay fail to start. If the program is accidentally interrupted, carry out the followingprocedure to restart the instrument.

(1) Turn OFF SEM of the display power switches. (2) A peeping sound will be heard to indicate changeover to the backup power

supply. Wait about 5 minutes for the peeping sound to disappear after thebackup power is used up.

(3) Turn ON SEM of the display power switches again. Then carry out theprocedures from (2) below.

(2) Upon turning on the above switches, the message “Console Login:” will appear.Now enter “cdsem” and the system program is automatically loaded and the user loginscreen appears. But if a wafer is already in the system at power-on, then the wafer mustbe returned to the cassette. A message indicating this will appear, and the login screenwon’t appear until the wafer returns to the cassette. This is explained at the “initial” sectionof the window operation.

7.1.1

7 - 2

(3) LoginThe message “Console Login:” will appear. Enter “cdsem” and the user login screenshown in Fig. 7-1 will appear automatically. So move the cursor to the relevant item, key ina user name and press the Return key. Key in a password in the same way.

Fig. 7-1 User Login Screen

Note on Instrument Startup:

If any error occurs at startup of the system (except when a wafer is already set), thesystem does not perform normal operation. In this case, carry out logging-in throughthe User Login screen and then stop the system as described in Section 7.2.Thereafter, check suspect points that might have caused the error.If the error cannot be removed even after restart of the system, notify the qualifiedservice engineer.

7.1 Startup

User login name entry area

Password entry area

7 - 3

When the user name and password are correctly entered, the work manager screen shownin Fig. 7-2 will appear at the bottom of the CRT. The usable functions vary with the username. There are three user levels -- Operator, Staff and Manager. If login is not made atStaff or Manager level, then file editing and the like cannot be done. And if “emi” is loggedin for both user name and password at shipment of the instrument, then login can be madeat Manager level. In other cases, the instrument should be used after having the managercarry out the user registration.

Fig. 7-2 Work Manager Screen

7.1.2 Startup from Complete Shutdown

Take the following steps for turning on power from a completely stopped status.

(1) Make sure the power switch on the user’s switchboard is turned ON.

(2) Make sure the MAIN switch on the power supply unit is OFF (flipped down). If turned ON,then turn the MAIN switch to OFF and push in the white section of each switch.

(3) Turn ON the MAIN switch while holding down the PUSH switch. Next turn ON the IP/FLPOWER, STAGE POWER, DISPLAY POWER , RP2 POWER, RP1 POWER and EVACPOWER switches.

(4) Turn ON (flip up), one at a time, the IP1, IP2 and IP3 ion pump power switches on thepower supply unit (do not turn on these three switches simultaneously).

(5) Turn ON the IP/HV and EVAC power switches of the display section. (6) While watching the ION-PUMP meter on the evacuation system control panel (main unit),

press, one at a time, the RESET switches of IP1, IP2 and IP3. If the IP1 to IP3 lamps donot come on (or repeat coming on and then going off 5 times in succession), then press theRESET switch again (do not press the three RESET switches simultaneously). The ionpumps should then start. If they still do not start, then contact the service agent.The instrument is evacuated automatically. Check if the normal status given in thefollowing table is attained.

7.1.2

7 - 4

Table 7-1 Normal Status of Evacuation System

Check Item Normal Status Remarks

IP1 vacuum degree(electron gun chamber)

< 2 5 10-7 PaIP1 lamp lit

Check meter reading on evacuationcontrol panel.

IP2 vacuum degree(intermediate chamber)

< 5 5 10-6 PaIP2 lamp lit

"

IP3 vacuum degree(condenser lens)

< 5 5 10-5 PaIP3 lamp lit

"

Pe1 vacuum degree(specimen chamber)

< 6 5 10-3 PaPi1/Pe1 lamps lit

"

Pe2 vacuum degree(loader chamber)

< 1 5 10-2 PaPi2/Pe2 lamps lit

"

TMP1 TMP1/NORM lamps lit "

TMP2 TMP2/NORM lamps lit "

RP1, RP2 Lamps lit "

AV4, AV6 to AV8 Lamps lit "

AV3 Lamps lit or extinguished "

Valves other than above Lamps extinguished "

APS Lamp lit "

Air pressure 600 to 880 kPa Check pressure gauge of air pipingprovided by customer.

N2 gas pressure 400 to 880 kPa "

Vacuum source 13 to 40 kPa "

(7) Start the instrument by the procedure in 7.1.1.

(8) Apply the electron beam. But if the electron gun has not been evacuated by the ion pumpsfor 24 hours or longer, then baking will be necessary. Following is the procedure for beamapplication.Click HV Controller on the Maintenance pull-down menu of the work manager screen.Select ON of the HV Controller screen.The initial values of filament current, accelerating and extracting voltages will now beapplied. The microscope requires about 40 minutes until the electron beam stabilizes.Be sure to carry out axial alignment after finishing this section.Refer to section 8 for the axial alignment.

7.1 Startup

7 - 5

7.1.3 Startup After Recovery from Power Failure or Emergency Stop

When the instrument has been completely stopped by a power failure or by operation of theemergency stop switch, although the system power supply is turned off, power is supplied to theworkstation for about 5 minutes from the backup power supply for file protection. An intermittentpeep sound is generated during this period to inform the operator that the backup power supply isoperating. To restart the instrument after recovery from the power failure or emergency stop,take the following procedure.

(1) Turn OFF all the breakers and switches on the power supply unit.

(2) If the instrument has been stopped by the emergency stop switch, turn this switch rightwardto its original position.

(3) Make sure the backup power supply has stopped and the peep sound is no longer emitted.The backup power supply operates for about 5 minutes after the instrument comes to acomplete stop.

(4) Carry out steps (1), (2) and (3) in 7.1.2.

(5) Turn ON the IP/HV and STAGE power switches of the display section.

(6) The specimen stage is initialized.

(7) Turn ON the EVAC and SEM power switches of the display section.

(8) Carry out steps (2) and (3) in 7.1.1.

7.2 Shutdown of Instrument

7.2.1 Normal Shutdown

At shutdown, be sure to remove the wafer from the instrument.

(1) Select Shutdown on the Maintenance menu of the work manager screen.

(2) Select Normal on the Shutdown window and click Execute . A message asking whether itis okay to execute will appear on the screen. By pressing the OK button, the normalshutdown procedure will start.

(3) After the SEM power is turned OFF, turn OFF the stage power.

NOTICE: After complete shutdown of the instrument, be sure to close the main valve ofthe vacuum source connected with the instrument.

7 - 6

7.2.2 Complete Shutdown of Instrument

At shutdown, be sure to remove the wafer from the instrument.

(1) Select Shutdown on the Maintenance menu of the work manager screen.

(2) Select Total on the Shutdown window and click Execute . By pressing the OK button inresponse to the inquiry, the shutdown procedure will start.

(3) After the SEM power is turned OFF, turn OFF the STAGE, EVAC and IP/HV switches onthe power switch panel.

(4) Turn OFF (flip down) the IP1, IP2 and IP3 switches on the ion pump power supply.

(5) Turn OFF (flip down) the OUTER BAKE POWER and INNER BAKE POWER switches onthe power supply unit.

(6) Turn OFF (flip down) the EVAC POWER, RP1 POWER, RP2 POWER, DISPLAY POWER ,STAGE POWER, IP/FL POWER and MAIN switches on the power supply unit.

(7) Turn OFF the power switch on the switchboard to cut off power to the instrument.

(8) With the above procedure the instrument is completely stopped. But to avoid airleak to theinstrument, do not stop the air source prepared by the customer.

NOTICE: After complete shutdown of the instrument, be sure to close the main valve ofthe vacuum source connected with the instrument.

7 - 7

NOTICE: The following is essential for complete shutdown of the instrument. Be sure totake this procedure.

Prerequisite for Shutdown

For completely shutting down the instrument and stopping the air source, attach the furnishedclamp to the AV-1 cylinder in order to maintain the electron gun vacuum

Fig. 7-3 AV-1 Cylinder Area

7.2.3 Shutdown at Power Failure

Carry out steps (3), (4), (5), (6) and (7) in 7.2.2 for complete shutdown of the instrument.(But note that even if these switches are not turned off, automatic reset will not be made at powerrecovery.)

7.2.3

Air tubes Clamp

ColumnLock nutAV-1 cylinder

8 - 1

8. IMAGE ADJUSTMENT

8.1 Optical Microscope Image

The optical microscope is used for observing a wafer at low magnification. Since the opticalmicroscope image provides a better S/N ratio than a low-mag SEM image, it is easier to locate theposition of the pattern to be measured. The magnification and visual field with an opticalmicroscope image are as follows.

Magnification Approx. 5110(fixed magnification)

Visual field Approx. 1.2 mm 5 1.2 mm

8.1.1 Adjustment of Optical Microscope (OM) Image

(1) Select Image Operation (Fig. 8-1) from the work manager menu (Fig. 7-2), and select OMfrom the Image menu.

(2) Select Stage Controller from the work manager menu, and move the stage to the waferpattern position.

(3) Select Beam Cont... (Fig. 8-2) from the Image Operation screen, and the Beam Controllerscreen will open. Click OM LUX and adjust image brightness with the OM LUX slide bar.

(4) Adjust the focus with the focus-adjusting slide bar on the Image Operation screen.

8.1.1

8 - 2

Fig. 8-1 Image Operation Screen

Fig. 8-2 Beam Controller Screen

Image selection

Cursor control

Image display

Focus adjustmentslide bar

Beam setting

OM LUX slide bar

OM LUX

8.1 Optical Microscope Image

8 - 3

8.1.2 Auto Adjustment of Optical Microscope (OM) Image

(1) Select Image Operation (Fig. 8-1) from the work manager menu (Fig. 7-2), and select OMfrom the Image menu.

(2) Select Stage Controller from the work manager menu, and move the stage to the waferpattern position.

(3) Select Beam Cont... (Fig. 8-3) from the Image Operation screen and the Beam Controllerscreen will open. Click Ref of the OM autoillumination adjusting reference and specify thedegree of illumination. This is settable in a range of 1 to 5, with 5 providing the maximumbrightness and 1 the minimum. Click Auto of B. & C. and the illumination is adjustedautomatically.

(4) Click Focus Auto (Fig. 8-4) at the lower part of the Image Operation screen, and the focuswill be adjusted automatically.

Fig. 8-3 Beam Controller Screen

Fig. 8-4 Image Operation Screen

Notes: 1. When there are not many features on the sample image on the screen, theaccuracy of auto focusing may be inadequate.

2. A large deviation in focus may indicate that the auto focus is not activated.In such case, first make a coarse adjustment with the focus-adjusting slide barand then execute the auto focus.

8.1.2

OM auto illuminationadjustment

Reference for OM autoillumination adjustment

Auto focus button

8 - 4

8.2 Condition Setting for SEM Image

Condition setting for the SEM image obtained with the electron beam consists of acceleratingvoltage and probe current settings. First the accelerating voltage is set, followed by the probecurrent.

(1) Select Image Operation from the work manager menu (Fig. 7-2), and click HV... on theImage Operation screen. As shown on the screen below (Fig. 8-5), enter the normallyused accelerating voltage at Set Vac using the keyboard (800 V for example).

(2) Next select the probe current range normally used at that accelerating voltage. High ,Middle and Low of Ip Mode indicate the probe current levels, and following are theapproximate ranges of each.High : 7 to 12 pAMiddle : 4 to 7 pALow : 2 to 4 pA

Click the appropriate probe current level, and carry out axial alignment with Alignment 1 and2. (Refer to 8.3.5 and 8.3.6 for this axial alignment.) When power is turned on aftershutdown, be sure to set up the Ip Mode again. By clicking Ip Range , the actual probecurrent range for the selected level is automatically measured and indicated.

(3) Finally enter the probe current to be used at Set Ip using the keyboard (5 pA for example).A current value within Ip Range is settable at Set Ip.

Fig. 8-5 HV Setup Screen

(4) Axial alignment of electron gun is done in Middle Ip Mode before the instrument is shipped.To use High or Low mode in step (2) above, axial alignment of electron gun is required.(For details of axial alignment, refer to 8.3.2-Axial Alignment of Electron Optics.)

8.2 Condition Setting for SEM Image

8 - 5

8.3 Axial Alignment of Electron Optics

8.3.1 Axial Alignment of Electron Optics

The extent of axial alignment of the electron optics varies with the condition at that particular time.Select and carry out appropriate steps of alignment. Fig. 8-6 shows the overall flow of electronoptics axial alignment and the criteria for alignment step selection. After taking any alignmentstep, be sure to carry out all of its subordinate (lower-priority) steps.

l After baking l After tip replacement l When desired probe current is not

obtained upon changing acceleratingvoltage (Set Vac)

l After exchanging objectivemovable aperture

l When Ip Mode is changed l When accelerating voltage (Set Vac)

is changed l When good SEM image is not

obtainable through axial alignmentwith Alignment 2 after changingprobe current (emission current)

l When probe current (emission current) ischanged.

Mechanicalalignments

Electricalalignments

Lowerpriority

Higherpriority

Fig. 8-6 Overall Flow of Electron Optics Axial Alignment

8.3.1

Axial alignment steps

Electron gun axial alignment

Condenser lens1axial alignment

Condenser lens2axial alignment

Objective movable apertureaxial alignment

Axial alignment usingAlignment 1

Axial alignment usingAlignment 2

Stigmator coil axial alignment

Registration of SEMcondition memory data

End

8 - 6

8.3.2 Axial Alignment of Electron Gun (carried out by service engineers only)

(1) Remove the front cover from the column.

(2) Attach four axial alignment knobs (furnished as accessories) to the electron gun assembly.

Fig. 8-7 Attachment Positions of Axial Alignment Knobs

(3) Click ALP on the Stage Controller screen to move the specimen stage to the alignmentspecimen position.

(4) Turn off excitation condenser lenses 1 and 2 (detach the connectors).

(5) Open the objective movable aperture (set to ‘0’).

(6) Click Align. Clear on the Beam Controller screen, and the electrical alignment is cleared.

(7) Key in a desired accelerating voltage at Set Vac on the HV Setup screen (800 V normally).Then select Middle of Ip Mode.

(8) Set magnification to a minimum ( 5600), and adjust focus with FOCUS knob or theCoarse/Fine slide bar on the Image Operation screen.

(9) Set B. & C. on Beam Controller screen to Manual. Select B. & C. and adjust the brightnessand contrast.

(10) Turn the electron gun alignment knobs to obtain the brightest grid image.

(11) Click None on Beam Controller screen.

This completes the axial alignment of the electron gun. Proceed to axial alignment of thecondenser lens.

8.3 Axial Alignment of Electron Optics

Electron gunalignment knob(´ 4)

8 - 7

8.3.3 Axial Alignment of Condenser Lens 1 and 2 (carried out by service engineers only)

(1) Axial alignment should be performed in the order of condenser lenses 1 and 2. Attach theCOND.1 connector.

(2) Set magnification to minimum level and adjust focus with FOCUS knob or with theCoarse/Fine slide bar of Image Operation screen.

(3) Turn the condenser lens alignment knobs and obtain the brightest grid image.

(4) Set magnification to 52000 and adjust focus as in step (2).

(5) Click Alignment 2 on the Beam Controller screen.

(6) Turn the condenser lens alignment knobs to minimize the SEM image movement (image willmove concentrically).

(7) Click None on the Beam Controller screen.Attach the COND.2 connector, and carry out adjustment starting from step (2).

(8) This completes the axial alignment of the condenser lens. Proceed to axial alignment ofthe objective movable aperture.

8.3.4 Axial Alignment of Objective Movable Aperture

(1) Set B. & C. on Beam Controller screen to Auto. Click Align. Clear to clear the electricalalignment.

(2) Set the movable aperture select knob to one of 1 to 4.

(3) Set magnification to minimum level.

(4) Adjust the focus.

(5) Click Alignment 2 on the Beam Controller screen.

(6) Using the objective movable aperture fine adjust knobs X and Y, minimize the imagemovement on the CRT (so image will move concentrically).

(7) Click None on the Beam Controller screen.

(8) Set magnification to 550000.

(9) Repeat steps (4) to (7) above.

8.3.3

8 - 8

8.3.5 Axial Alignment Using Alignment 1

This is an electrical alignment, and is used when changing accelerating voltage or Ip Mode.

(1) Click Align. Clear on the Beam Controller screen.

(2) Click Alignment 1 on the Beam Controller screen.

(3) Set magnification to minimum level. Adjust X, Y slide bar on the Beam Controller screen sothe bright part through which the beam has passed comes to the screen center (Fig. 8-8).

Fig. 8-8 Axial Alignment Using Alignment 1

(4) After the adjustment, click None on the Beam Controller screen.

(5) Proceed to axial alignment using Alignment 2.

Fig. 8-9 Beam Controller Screen

8.3 Axial Alignment of Electron Optics

8 - 9

8.3.6 Axial Alignment Using Alignment 2

(1) Carry out focusing on the sample.

(2) Click Alignment 2 on the Beam Controller screen.

(3) Using the X, Y slide bar on the Beam Controller screen, minimize the movement of SEMimage (so image will move concentrically).

(4) Gradually increase magnification from minimum level to about 510000 while adjusting.

(5) After the adjustment, click None on the Beam Controller screen.

8.3.7 Axial Alignment of Stigmator Coil

(1) Carry out focusing on the sample.

(2) Click Stigma Align.X/Stigma Align.Y on the Beam Controller screen.

(3) Using the XX, XY (YX, YY) slide bar on the Beam Controller screen, minimize the movementof the SEM image.

(4) Adjust at a magnification of minimum level to 55000.

(5) After adjustment with Stigma Align.X, click Stigma Align.Y and minimize the movement ofSEM image in the same way.

(6) Click Alignment 2 on the Beam Controller screen and check if the image movement isminimum. If not minimized, repeat adjustment with Alignment 2, Stigma Align.X andStigma Align.Y until the movement is minimum.

(7) After the adjustment, click None on the Beam Controller screen.

8.3.8 Astigmatism Correction

(1) Manual AdjustmentAstigmatism is corrected by means of the STIGMA knob on the control panel.

-STIGMA- FOCUS

8.3.6

—STIGMA— FOCUS

Fig. 8-10 Positions of STIGMA and FOCUS Knobs

8 - 10

(2) Auto Stigma

To carry out the auto stigma function, click AST button on the Beam Controller screen.Before execution of this function, be sure to perform axial alignment as in 8.3.1. For thispurpose, click STP button on the Stage Controller screen to set up the astigmatismcompensation specimen position.During execution of the auto stigma sequence, the image is frozen and its magnification isswitched to 50k (display remains unchanged). When the auto stigma sequence iscompleted, the magnification is restored to the original level (which has been selected beforeexecution).

8.3.9 Focusing

(1) Manual Focus AdjustmentFocus is adjustable by means of the FOCUS knob on the control panel or by the slide bar onthe Image Operation screen. In the latter case, click Coarse to make a coarse adjustmentand Fine to make a fine adjustment.

Fig. 8-11 Image Operation Screen

8.3 Axial Alignment of Electron Optics

Image selection

High voltagesetting

Magnificationsetting

Beam setting

Focus-adjustingslide bar

8 - 11

(2) Auto Focus AdjustmentClick Focus Auto at the lower part of the Image Operation screen to execute autofocusing.Note that if the image showing contrast is too small, the autofocusing may not work properly,so it is recommended to adjust the magnification until the contrast portion takes up at least1/4 of the screen. In the case of auto measurement by way of recipe, autofocusing isexecuted automatically together with the autoaddressing function.

(3) Manual Astigmatism Correction and Focus AdjustmentManual correction of both astigmatism and focus is explained next. In this case the imagewill appear as in the photos upon adjusting the focus. First, set an entire-image-defocusedstate before the astigmatism correction.

Fig. 8-12 Images with Astigmatism and Defocused

Next adjust the stigmator knobs until the image becomes clear. And carry out focusing bythe aforementioned method and correct the astigmatism. Repeat the adjustment until theimage becomes clear. Finally adjust the focus again.

8.3.9

Partially focused Entire imagedefocused

Partially focused

8 - 12

8.3.10 Saving/Loading of SEM Condition Memory

Up to 20 SEM condition memory areas are available. The following data can be savedcollectively into the SEM condition memory.

• Accelerating voltage• Probe current• Probe current mode H/M/L• Retarding ON/OFF• Alignment 1 and 2• Stigma• Stigma alignment

For saving/loading SEM condition data,click the Manager... button on the Beam Controller screen.The SEM Condition Memory Manager screen will then appear. You can save/load the SEMcondition data through this screen.Before attempting to save the SEM condition data, be sure to complete axial alignment.In SEM condition data loading, you can set up the saved observation parameters (except probecurrent value) and axial alignment data.

8.3.11 Image Contrast and Brightness

(1) Manual AdjustmentSet B. & C. on Beam Controller screen to Manual (the pulldown menu will appear if Auto isclicked, so select Manual ).Upon clicking B. & C. , brightness and contrast are adjustable with the Brightness/Contrast slide bar.

(2) Auto AdjustmentSet B. & C. on Beam Controller screen to Auto . The gradation of Ref is as follows.

B. Ref 1 2 3 4 5brightness Brighter

C. Ref 1 2 3 4 5contrast Higher contrast

8.3 Axial Alignment of Electron Optics

Observation parameters

Axial alignment data

9 - 1

9. TROUBLESHOOTING

WARNING

· Voltages up to 100 V AC and 10 kV DC are used in thisinstrument. Touching internal parts may result in anelectric shock.

· If you remove the covers of column unit, control unit and/orpower unit and touch internal parts while the instrumentpower is turned on, there is a danger of fatal or seriousinjury due to electric shock.

· Before handling parts inside the instrument, be sure to turnoff the related power supply. If covers must be removedwith the power on, do not touch parts inside the units.

· If you accidentally touch moving parts inside theinstrument, there is a danger of your hand being caught orelse cut.

· Before removing the covers and handling parts inside themain unit, be sure to turn OFF the power.

· Do not touch hot sections such as oil rotary pump, turbomolecular pump, baking heater, or power unit and leakvalve inside the instrument, or you may be burned.

· Before handling hot sections, be sure to turn OFF therelated power supply and wait until the part cools downsufficiently.

· Particularly when replacing the oil in the rotary pump, thereis a danger of the oil splashing out while the pump itself isstill hot. Wait until the pump cools down before replacingthe oil.

9

9 - 2

WARNING

· If tubing is performed with N2 gas flowing out, and a largeamount of the gas is inhaled, it could cause breathingdifficulty, and in the worst case, could be fatal.Before carrying out tubing for the N2 gas, make sure toclose the main valve for the N2 gas.

· If a large amount of vaporized hexane (n-hexane) is inhaled,it may result in injury or breathing difficulty.

· In a place where hexane is used, be sure to ventilate welland be careful not to inhale in a large amount. Also wearan antigas mask or the like if necessary.

· Be careful not to ignite vaporized hexane because it mayexplode.

· When hexane is used, be sure to ventilate the place welland don’t use a flame in the vicinity.

· If hexane is mistakenly swallowed or comes into contactwith the skin or eyes, it may affect the nervous system invarious ways such as paralysis of the senses, difficulty inwalking, etc. due to stimulation.

· When hexane is used, be sure to ventilate the place well,and depending on the conditions, use an air aspirator,protective goggles and protective gloves and clothes.

9. TROUBLESHOOTING

9 - 3

9.1 Evacuation System Abnormalities

Fault Symptom Probable Cause Remedy

Power failure occurred

Fuse has blown Contact service engineer.

Evacuation system stopsoperating

Air pressure for driving valves has dropped below600 kPa (APS lamp extinguished on evacuationcontrol panel).

Leakage of air(a) Due to incomplete closing of loader

chamber door(b) Due to contamination of seal face and

gasket of loader chamber door

Faulty Pirani gauge Contact service engineer.

Faulty oil rotary pump(a) Very little (or excessive) RP oil(b) RP motor doesn’t work

Malfunction of evacuation system valve(a) Air pressure drop or air leak(b) Defective valve

Contact service engineer.

Specimen chambervacuum does not rise(low vacuum range)

Malfunction of leak valve (LV1)

TMP performance has degraded, or normal TMPoperation impossible.

Contact service engineer.

Malfunction of evacuation system valve(a) Air leakage(b) Faulty valve

Contact service engineer.

Faulty Pirani or Penning gauge Contact service engineer.

Specimen chamber andloader chamber vacuumdoes not rise(high vacuum range)

Vacuum leakage(a) Leak valve (LV1) faulty or seal face

contaminated(b) Seal face contaminated on loader chamber

lid

If leakage doesn’t stop,contact service engineer.

Faulty ion pumpIntermediate chambervacuum does not rise(high vacuum range: 10-3 to 10-6 Pa)

Vacuum leakage

Contact service engineer.

9.1

9 - 4

(cont'd)

Fault Symptom Probable Cause Remedy

Faulty ion pump

Poor performance of ion pump*

Electron gun chambervacuum does not rise(ultrahigh vacuum range: 10-5 to 10-7 Pa) Vacuum leakage

Contact service engineer.

NoteH: When the instrument is used for a long time, the ion pump (inner wall, pump element, etc.) is increasingly contaminated and its performance is degraded. If the vacuum degree is not improved by baking the ion pump, regenerative treatment is required. When the life of the ion pump has expired, replacement of elements is required. In case the prescribed vacuum is unobtainable although neither a leak nor other cause is located, contact your service engineer.

9.2 Abnormal Specimen Stage/Loader

Perform check according to Fig. 9-1.After the specimen exchange (XC) chamber is opened, the wafer transfer arm enters the XCchamber. Under this condition, if the instrument is stopped due to power failure or otherabnormality, turn power on again. At this step, initialization may not come to a normal end.In this case, open the right cover of auto loader, and press the RESET key of wafer transfercontroller. Then, after resetting in this manner, shut down the instrument and turn power onagain.If a wafer is placed on the transfer arm, press the STOP key when the arm comes to a properposition after resetting. Then, after removing the wafer, press the RESET key again.

Wafer Transfer Controller

RESET KEY

STOP KEY

9.2 Abnormal Specimen Stage/Loader

9 - 5

Fig. 9-1 Checks on Specimen Stage/Loader

9.2

Failure ofstage/loader

Malfunctionof stage

Stage defective

Malfunctionof loader

Stage drivemechanismdefective

Drivemechanismdefective

Loader or airlock improper

Wafer holderchuck/unchuckimproper

(1) Torque fluctuation due to contamination ofguide sliding face

(2) Abrasion of wafer holder guide bearing

(3) Abrasion of sliding face

(1) Stepping motor

(2) Increase in backlash of ball screw

(3) Backlash/damage of lateral coupling

(4) Torque increase due to contamination with oil

(5) Abrasion of ball screw bearing

(6) Increase in output torque of magnetic seal

(7) Looseness of stage joint

(8) Backlash of linear guide/insufficient pre-load

(9) Malfunction of limit switch

(1) Malfunction of air cylinder

(2) Expiration of bellows life

(3) Abrasion of packing for seal

(4) Abrasion of drive shaft and link plate

(5) Defective limit switch

(6) Malfunction of solenoid valve for air

(1) Stepping motor

(2) Increase in backlash of ball screw

(3) Backlash/damage of lateral coupling

(4) Torque increase due to contamination with oil

(5) Abrasion of ball screw bearing

(6) Increase in output torque of magnetic seal

(7) Backlash of linear guide/insufficientPre-load

(8) Malfunction of limit switch

(1) Abrasion of bearing in chuck section

(2) Malfunction of solenoid valve for air

(3) Defective photointerrupter

(4) Increase in output torque of magnetic seal

9 - 6

9.3 Abnormal SEM Image

9.3.1 Abnormal Emission Current

(1) Fluctuation of Emission Current(a) Confirm that the vacuum degree of IP1 is better than 1 5 10-7 Pa.

When the emission current fluctuates due to deterioration of vacuum in the electrongun chamber, carry out baking. Contact your service engineer.

(b) Abnormal High Voltage SupplyContact your service engineer.

(2) No Emission Current (image not displayed on CRT)(a) Damage of FE tip: Contact your service engineer.(b) Defective emission current meter: Contact your service engineer.

(3) Fluctuation of Acceleration Voltage (Vac)Contact your service engineer.

9.3.2 Absence of Image on CRT

(1) Poor electron gun alignment

(2) The AV1 valve won’t open. Contact your service engineer.

(3) Faulty Head AmplifierIf so, CRT brightness cannot be changed by turning the BRIGHTNESS knob (after modechange from AUTO to MAN). Contact your service engineer.

(4) The post-stage acceleration high voltage is not applied.

(5) The photomultiplier high voltage is not applied.

(6) Excessively counterclockwise turning of CONTRAST knob (in manual mode)

(7) Poor adjustment of FOCUS (objective lens) controls

(8) The electron extracting voltage is not applied.

(9) Damage of FE tip (no emission current obtained)

(10) Shortage of secondary electrons due to extremely low emission current

(11) The accelerating voltage is not applied.

9.3 Abnormal SEM Image

9 - 7

(12) Poor Adjustment of Objective Lens Movable ApertureSet the longitudinal fine control knob of the objective lens movable aperture to aboutmidpoint and the objective lens movable aperture to position 0. If the image does notappear on the CRT yet, check further.

(13) Too high magnification

(14) Each vacuum degree of IP1, IP2 and IP3 does not reach the following value.

S-8000 series S-7000 seriesIP1: 2 5 10-7 Pa IP1: 1 5 10-8 PaIP2: 5 5 10-6 Pa IP2: 2 5 10-6 PaIP3: 5 5 10-5 Pa IP3: 7 5 10-5 Pa

9.3.3 Noisy Image

(1) Damaged ScintillatorReplace the scintillator. Contact your service engineer.

(2) Astigmatism Correction ImpossibleDefective astigmatism correcting circuit:

Contact your service engineer. (Astigmatism of the image does not change whenturning the STIGMATOR (X, Y) knobs fully counterclockwise and clockwise.)The magnification should be 510,000 or so.

(3) Poor centering of objective lens movable aperture

(4) Dirty Objective Lens Movable ApertureReplace the objective lens movable aperture.

(5) Poor Axial AlignmentRetry to align the electron gun with the lens system.

9.3.3

9 - 8

9.4 Abnormal Optical Microscope (OM) Image

9.4.1 Absence of OM Image

(1) OM image is not selected on the image operation screen. Make changeover to OM image.

(2) Improper BrightnessAdjust the brightness with the OM LUX knob of the beam controller.

(3) The brightness is not changed by adjusting the above knob.The lamp for OM is burnt out. Replace the lamp.

(4) The specimen is not located at the optical microscope position.Move the specimen to the ALP/CLP position or the position of pattern on the wafer with thestage controller.

(5) The optical microscope is out of focus. Adjust the focus on the image operation screen.

9.5 Display Unit Fails

(1) Blowing of Power FuseReplace the fuse (Contact your service engineer).

(2) Defective Display Unit (Contact your service engineer.)For any other trouble, contact your service engineer.

9.6 Software Error

If the software operation is erroneous or the behavior of software seems to be abnormal, notifythe qualified service personnel of the symptom and operating conditions.In such a case, it is advisable to provide the log data containing the records of internalcommunications and operations of the computer. Using the log data, the service personnel mayfind out the cause of trouble more promptly. So, in the manner mentioned below, output the logdata onto a floppy disk and give it to the service engineer.Although the records of internal communications and operations of the computer are contained inthe log data, it does not hold the process conditions of IDW/IDP file and other condition data.Note also that the log data can contain the communication/operation records corresponding tojust a short period of approx. 10 minutes before execution of the Logging command.

9.4 Abnormal Optical Microscope (OM) Image

9 - 9

9.6.1 How to Save Log Data onto Hard Disk (HD)

The log data is retained in the main memory of the workstation. Therefore, it will be lost whenpower is turned off. First, save the log data onto the HD immediately after occurrence of atrouble in software.On the console, press the OFF button for more than three seconds repetitively three times asshown below. This button action saves the log data onto the HD. If the screen is locked, takethis procedure to carry out logging. While the log data is saved onto the HD, eight LEDindicators on the front of workstation (on the periphery of the front panel of the display) blink forseveral seconds. Make sure of blinking of these indicators. Then, restart the system in themanner described in 9.6.3.

9.6.2 How to Output Log Data onto Floppy Disk

After saving the log data onto the hard disk as instructed in 9.6.1, you can output it to a floppy disk(FD).First prepare a 3.5-inch 1.44 MB floppy disk. Then start the Utility-Accessories-Log to FD.A message confirming whether or not FD is set will appear. Remove the write protection of theFD and put it into the FD drive of the workstation. Operate according to the messages displayed,and the FD will be initialized in the specific format and the log data will be stored in it. It takesabout six minutes to output the log data onto the floppy disk. The floppy disk on which the logdata has thus been stored should be given to the service engineer.

Note that just one set of log data can be stored on the floppy disk.Remember that the floppy disk is formatted before the log data is output to it. So, beforeattempting to output the log data to the floppy disk, make sure that it contains no other importantdata.

For morethan 3

For morethan 3

For morethan 3

ON ON ON

For less than2 seconds

For less than2 seconds

Execution of logging

9.6.1

9 - 10

9.6.3 Restart After Software Error

If an error has occurred in the software operation for some reason, restart the system in thefollowing procedure, starting from step (1). Note that this procedure is for restarting after theoccurrence of a software error, and should not be used normally.

(1) When operation can be done with mouse:(a) Select Shutdown from the Maintenance menu of the work manager.(b) Select Normal on the Shutdown window, and click Execute . A prompt will appear

asking whether you want to execute, so press OK, then the termination process willstart.

(c) The SEM power supply will turn off automatically (see Fig. 2-11 in 2.4.2). Turn on theSEM power supply again.

(d) When “Console Login:” appears, enter cdsem in succession and press the Return key.The system is restarted.

(2) When key entries can be made:(a) Press Shift , CTRL and Break keys simultaneously, and the window system is

terminated.(b) Enter nxshut from the keyboard and press the Return key.(c) Press CTRL and d keys together, and carry out the process twice. “Console Login:”

will then appear.(d) Turn off the SEM power supply. Wait about 10 seconds, and turn on the SEM power

supply again.(e) In succession to “Console Login”, appears, enter cdsem and press the Return key.

The system is restarted.

(3) When key entries cannot be made:(a) Turn off the SEM power supply. The display power supply will be cut off, and the

system will be terminated automatically. Wait about 5 minutes for the peeping soundto end, and turn on the SEM power supply again.

(b) When “Console Login:” appears, enter cdsem in succession and press the Return key.The system is restarted.

9.6 Software Error

10 - 1

10. MAINTENANCE

10.1 Consumables and Spare Parts

10.1.1 Consumables

The items shown in Table 10-1 should always be on hand for normal operation.

Table 10-1 Consumables

Part No. Part Name Use Remarks

567-4805 Vacuum grease (Y-VAC 2) For vacuum seal

Hexane (C8H14) For part cleaning Contained in 500 cc bottle,special grade

567-0995 Objective lens aperture plate(0.02 mm in diameter 54)

For objective lens

567-0994 Schottky tip For electron gun

830-4183 Scintillator For SE detector

Polyethylene gloves For part handling

565-1026 RP oil For direct-connection-type RP

4 L contained, manufactured byEdwards Japan, Co. (*)

566-1588 RP alumina (H02600050) For foreline trap Contained in 0.45 kg can(*)

545-1214 Grease For lubrication of driveparts in vacuum

20 g contained

567-6514 Thermal paper For printer

567-1488 Halogen lamp For optical microscope

567-3307 Fixed aperture(0.7 mm in diameter)

Located at the lowerpart of AV1 valve

(*) These items are required only when a rotary pump is used for pre-pumping.

10.1.1

10 - 2

10.1.2 Spare Parts

The items shown in Table 10-2 must be prepared for long-term operation. Select a properquantity in consideration of the application of each part.

Table 10-2 Spare Parts

Part No. Part Name Use Remarks

K439000 Penning gauge For vacuum level indication

567-6553 EWS backup power supply For protection of workstation

271-3162 CPU backup battery For data memory

567-6673 Mouse For workstation operation

567-0881 Solenoid valve (upper) For evacuation valve operation

567-0882 Solenoid valve (lower) For evacuation valve operation

580-4614 Air filter For filtering at N2 leakage

567-2437 Standard reference specimen For axial alignment

567-0942 Laser diode unit For Z sensor

567-3374 Load-lock transfer arm For wafer transfer For S-8840/S-8640

10.2 Cautions on Maintenance

Specialists will take charge of maintenance when contracted separately. However, formaintaining the specifications and performance of the instrument, the following cautions must beobserved in addition to the precautions given at the beginning of this manual.

(1) The customer is not allowed to disassemble the components (other than permitted in theinstruction manual) or modify them. Otherwise the original performance might not beavailable again.

(2) Do not allow dust, particularly metal powder to enter the inside of each component.

(3) Do not give strong shocks or vibrations to the mainframe.

10.2 Cautions on Maintenance

10 - 3

10.3 Periodic Inspection

Table 10-3 lists check items required for operating the instrument normally. For details ofcheck, contact your service engineer.

It is recommended to make a contract on maintenance service.

Table 10-3 Periodic Check

Responsible personnel: , and indicate user, Hitachi’s service engineer andunit vender's engineer respectively.

No.Frequency of

CheckCheck Item Responsibility Remarks

Daily(at startup)

1. Cleaning:Outside of loader chamber, instrumenttable, etc.

2. Check of vacuum degree, air pressure andN2 gas pressure

3. Calibration of measuring accuracy

1

Every 6 to 8 hours(at shutdown)

Check of vacuum degree, air pressure and N2

gas pressure

2 Weekly Check of electron-optical axis

3 Monthly 1. Cleaning:Exterior of instrument and control panel

2. Check of electron-optical axis3. Check of RP oil volume

4 Every 1.5 months Change of objective movable aperture selector

5 Biannually 1. Lubrication to stage drive mechanism2. Replacement of objective movable aperture

plate3. Check and greasing of evacuation valves4. Replacement of RP oil5. Replacement of alumina in foreline trap for

RP6. Maintenance of keyboard, mouse and

printer7. Cleaning inside loader chamber (including

AV3 and arm rotating mechanism.)

At charge*

At charge*

At charge*

At charge

6 Every 9 months 1. Replacement of electron gun cathode2. Replacement of fixed apertures of electron

optics

At chargeAt charge

7 Yearly 1. Replacement of scintillator2. Replacement of standard specimen

At chargeAt charge

10.3

10 - 4

(cont'd)

No.Frequency of

CheckCheck Item Responsibility Remarks

8 Biennially 1. Replacement of airlock valve (AV1, LV1)2. Replacement of solenoid valve unit3. Replacement of hard disk in computer4. Replacement of keyboard for computer5. Replacement of air filter6. Replacement of control CRT7. Replacement of uninterruptible power

supply for EWS8. Check and greasing of auto loader9. Check and greasing of orientation flat

sensor10. Replacement of backup power supply for

ion pump

At chargeAt chargeAt chargeAt chargeAt chargeAt chargeAt charge

At chargeAt charge

At charge

Note *: Check Item 1, 3 and 6 in No. 5 above will be carried out at charge at more than 1 year afterinstallation.

10.3.1 Evacuation System

(1) Check of Vacuum DegreeNormal status (evacuated status) of the evacuation system is as listed below.

Table 10-4 Normal Status of Evacuation System

Check Item Normal Status Remarks

IP1 vacuum degree(electron gun chamber)

< 2 5 10-7 PaIP1 lamp lit

Check meter reading on evacuation control panel.

IP2 vacuum degree(1st intermediate chamber)

< 5 5 10-6 PaIP2 lamp lit

Check meter reading on evacuation control panel.

IP3 vacuum degree(2nd intermediate chamber)

< 5 5 10-5 PaIP3 lamp lit

Check meter reading on evacuation control panel.

Pe1 vacuum degree(rear part of specimen chamber)

< 6 5 10-3 Pa Check meter reading on evacuation control panel.

Pe2 vacuum degree(lower part of loader chamber)

< 1 5 10-2 Pa Check meter reading on evacuation control panel.

Air pressureN2 gas pressureVacuum source pressure

490 kPa to 880 kPa392 kPa to 880 kPa13 kPa to 40 kPa

Check pressure gauge of air piping provided bycustomer.

(2) Maintaining Ultrahigh Vacuum in Electron Gun ChamberIf the normal vacuum degree shown in Table 10-4 is unavailable, request the serviceengineer for baking of the electron gun chamber.

(3) Maintaining High Vacuum in Specimen Chamber and Loader ChamberIf the normal vacuum degree shown in Table 10-4 is unavailable, contact the serviceengineer.

10.3 Periodic Inspection

10 - 5

(4) Maintenance of RPPeriodically carry out maintenance of the RP with reference to 10.3.4.

10.3.2 Replacement of Objective Movable Aperture

WARNING

· If a large amount of vaporized hexane (n-hexane) isinhaled, it may result in injury or breathing difficulty.

· In a place where hexane is used, be sure to ventilate welland be careful not to inhale in a large amount. Also wearan antigas mask or the like if necessary.

· Be careful not to ignite vaporized hexane because it mayexplode.

· When hexane is used, be sure to ventilate the place welland don’t use a flame in the vicinity.

· If hexane is mistakenly swallowed or comes into contactwith the skin or eyes, it may affect the nervous system invarious ways such as paralysis of the senses, difficulty inwalking, etc. due to stimulation.

· When hexane is used, be sure to ventilate the place well,and depending on the conditions, use an air aspirator,protective goggles and protective gloves and clothes.

(1) Select EVAC controller from Maintenance of the work manager.

(2) Click the SC-AIR button of the EVAC controller window.

(3) Wait 20 minutes until the aperture cools down to near the room temperature.

(4) N2 gas is automatically introduced into the specimen chamber and loader chamber.The procedure is finished when the lid of the specimen exchange chamber opens.

(5) During automatic operation in step (4) above, remove the front cover of the microscopecolumn.

(6) Remove the four M6 screws which retain the flange of the aperture assembly, disconnectthe heater power cable, and pull out the entire assembly slowly while keeping it horizontal(see Fig. 10-1).

10.3.2

10 - 6

(7) Place an aluminum foil of about 20 5 20 cm on a table. All parts removed in thefollowing steps should be placed on the foil.

(8) Remove the aperture support retaining screws with a watchmaker’s screwdriver (thesecond smallest one).

Fig. 10-1 Objective Movable Aperture

(9) Remove the aperture support with tweezers.

(10) Remove the objective aperture plate with tweezers.

(11) Clean the aperture support and aperture holder by means of absorbent cotton (wound on abamboo stick) and hexane. Cleaning should be done meticulously.

(12) Take out the aperture plate from a small bottle and mount it on the aperture holder.

(13) Place the aperture support on the aperture holder and slightly tighten the aperture supportretaining screw.

Aperture support

Aperture plate (P/N 567-0995)

Aperture supportFlange retaining screw

Aperture holder

Flange

Aperture supportretaining screw

Up

Down

Heater power cable

10.3 Periodic Inspection

10 - 7

(14) After confirming that the aperture plate is exactly centered, securely tighten the aperturesupport retaining screw. Also make sure that the aperture plate is retained completely bythe aperture support.

(15) Insert the aperture assembly straight into the flange. Be careful not to insert the apertureassembly upside down.

(16) Tighten the four flange retaining screws and connect the heater power cable.

(17) Click the SC-EVAC button on the Evacuation Controller .

(18) The specimen chamber and loader chamber are automatically evacuated. When thevacuum degree shown in Table 10-4 is satisfied, evacuation is completed.

10.3.3 Check Lists

Keep copies of the daily check list and periodic check list at an easy-to-access location near theinstrument.

10.3.3

Dai

ly C

heck

Lis

t

Dat

eN

ote:

C

heck

in th

e pe

riodi

c ch

eck

list m

ust a

lso

be p

erfo

rmed

.

No

.C

he

ck I

tem

12

34

56

78

910

1112

1314

1516

1718

1920

2122

2324

2526

2728

29

30

31

1Li

t sta

tus

of IP

1, 2

and

3 la

mps

2IP

1 p

ress

ure

< 2

5

10

-7 P

a

3IP

2 p

ress

ure

< 5

5

10

-6 P

a

4IP

3 p

ress

ure

< 5

5

10

-5 P

a

5P

e1

pre

ssu

re <

6

5

10

-3 P

a

6P

e2

pre

ssu

re <

1

5

10

-2 P

a

7A

ir p

ress

ure

= 4

90

kP

a(5

to

9 k

gf/

cm2 )

8N

2 g

as

pre

ssu

re =

39

2 k

Pa

(4 t

o 9

kg

f/cm

2 )

9R

P o

il vo

lum

e

10C

lea

nin

g o

f o

uts

ide

of

loa

de

r ch

am

be

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11E

lect

ron

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tics

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alib

rati

on

of

me

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rin

g a

ccu

racy

Mo

nth

ly C

he

ck I

tem

No

.C

he

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tem

Re

spo

nsi

bili

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nt

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er

10-8

10.3 Periodic Inspection

. .

. .

Per

iodi

c C

heck

Lis

tE

nter

the

date

of e

xecu

tion

No.

Fre

qu

en

cyC

he

ck I

tem

Da

te

Re

spo

nsi

bil

ity

12

34

56

78

910

1112

1314

1516

1718

1920

2122

2324

1C

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ck o

f e

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ron

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tica

l a

xis

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sto

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stru

me

nt

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3

Mo

nth

ly

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eck

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oil

vo

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ust

om

er

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very

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en

t o

f b

ack

up

po

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ly f

or

ion

pu

mp

Se

rvic

e e

ng

ine

er

At

cha

rge

Not

e:C

heck

s in

item

s no

. 5, 7

and

10

will

be

char

ged

at la

ter

than

1 y

ear

afte

r in

stal

latio

n.

10 - 9

10.3.3

Dai

ly C

heck

Lis

t (ca

sset

te-t

o-ca

sset

te a

uto

load

er)

Dat

e

No

.C

he

ck I

tem

12

34

56

78

910

1112

1314

1516

1718

1920

2122

2324

2526

2728

29

30

31

1V

acu

um

so

urc

e p

ress

ure

P =

13

to

40

kP

a (

10

0 t

o 3

00

To

rr)

(pre

ssu

re g

au

ge

of

air

pip

ing

pro

vid

ed

by

cust

om

er)

2C

lea

nin

g o

f e

xte

rio

r o

f a

uto

loa

de

r

3C

lea

nin

g o

f va

cuu

m c

lam

p o

n t

ran

sfe

ra

rm

Not

e:A

bsol

utel

y av

oid

clea

ning

in it

ems

no. 2

and

3 w

hen

the

auto

load

er is

run

ning

. O

ther

wis

e th

e tr

ansf

er r

obot

may

inju

re th

e hu

man

bod

y or

the

tran

sfer

arm

may

be

dam

aged

.

10.3 Periodic Inspection

10 - 10

10 - 11

10.3.4 Rotary Vacuum Pump (option)

(1) Name and Function of Each Part

²

±

°

®¬ ¯­

Fig. 10-2

¬ Air inlet­ Gas ballast valve

Prevents contamination/deterioration of oil due to condensed vapors (water/solvent).® Pump oil inlet

From here, oil is injected into the oil box.¯ Air outlet

Exhausts gas sucked through the air inlet.Kept open to atmosphere.

° Oil level gaugeUsed to check the oil volume and contamination in the oil box.

± Oil drainDischarges oil contained in the oil box.

² Carry handle

10.3.4

10 - 12

(2) Check of Oil Volume and Replacement of Oil

WARNING

· 100 V AC is supplied to the oil rotary pump. Touching themetallic terminal part of the power cable may result in fatalor serious injury due to electric shock.

· Do not touch the rotary pump itself nor its cover while thepump is operating, or you may be burned.

· Before carrying out maintenance on the rotary pump, besure to turn OFF the EVAC power supply on the displayunit and wait until the pump cools down sufficiently.

To lengthen the pump life and maintain the highest performance at all times, carry out thefollowing maintenance and inspection.

Table 10-5 Maintenance and Inspection

Maintenance/Check Item

Frequency Confirmation Maintenance

(1) Oil level Daily The oil level must be between MIN andMAX of the level gauge.

Replenishment of oil

(2) Contamination ofoil

Daily Check the degree of contaminationthrough the level gauge. (Replace oilbiannually.)

Replacement of oil

(3) Clogging of filter Biannually Check the degree of filter clogging. Cleaning of filter

10.3 Periodic Inspection

10 - 13

(a) Replenishment of Oil1) Detach the cap of the oil inlet by turning it

counterclockwise.2) While watching the level gauge, inject oil

through the oil inlet so that the oil level isapproximately 80% of the level gauge.

3) Upon completion of oil injection, securelytighten the cap by turning it clockwise.

(b) Replacement of Oil1) Detach the cap of the drain by turning it

counterclockwise with a blade-edgedscrewdriver. Oil will then be drained.In so doing, prepare an oil receiver andplace it under the drain.

2) After completely draining oil, securelytighten the cap of the drain.

3) Introduce oil through the oil inlet.

(c) Cleaning of Filter1) Detach the air inlet adapter.2) Remove the snap ring from the air inlet

with a blade-edged screwdriver.3) Remove the filter under the snap ring and

eliminate contaminants from the filter.4) Upon completion of cleaning, return the

removed parts as before.

10.3.4

Oil inletAir outlet

Oil drainOil level gauge

Pump

Oil receiver

Oil drain

Desk

Air inlet adapter

Snap ring

Filter

10 - 14

(3) Maintenance of Foreline TrapThe foreline trap is intended to prevent oil from flowing backward into the vacuumcontainer.It employs special active alumina which absorbs oil vapors and collects at least 99.9% ofoil which flows backward.

· How to Put in Alumina (FL20K)1) Detach cap a from the mainframe by turning it counterclockwise and take out

basket e.2) Remove snap ring d from the basket with a blade-edged screwdriver and detach

the aluminum cap.3) Fill the basket with the furnished alumina to about four-fifths full.4) Return the removed parts as before.

(4) TroubleshootingIf any abnormality given below occurs, trace its cause and take proper countermeasuresaccording to the following troubleshooting table. If the abnormality persists after takingcountermeasures, contact your service engineer.

Symptom Check Remedy

Power supplied at primary side? Supply power at primary side.

Power cord burnt out? Repair power cord.

Motor does not rotate whenpower plug is inserted intoreceptacle.

Bearing damaged?Stator winding disconnected?

Contact your service engineer.

Circuit breaker is actuated. Motor heated.Temperature sensor actuatescircuit breaker

Contact your service engineer.

Leak caused in piping? Locate leak and repair piping.

Filter clogged? Eliminate contaminants from filter.

Vacuum degree is deteriorated.

Oil contaminated? Replace oil.

Tightening bolt loosened? Tighten bolt.Abnormal sound is emitted.

Bearing damaged?

Fan deformed?

Contact your service engineer.

Ventilating hole blocked? Clean ventilating hole or eliminateforeign matter from it.

Temperature rises appreciably.

Fan deformed? Contact your service engineer.

Snap ring dBasket eO-ring

Spring

Cap a

Mainframe

10.3 Periodic Inspection

I - 1

INDEX

AAbnormal emission current ..................................................................................................... 9-6Abnormal optical microscope image ....................................................................................... 9-8Abnormal SEM image ............................................................................................................. 9-6Abnormal specimen stage/loader............................................................................................ 9-4Alignment 1............................................................................................................................. 8-8Alignment 2............................................................................................................................. 8-9Allowable vibration .................................................................................................................. 1-6Appearance of instrument system........................................................................................... 2-1Astigmatism correction............................................................................................................ 8-9Auto focus............................................................................................................................. 8-11Auto loader ........................................................................................................................... 2-15Auto Stigma .......................................................................................................................... 8-10Auto transformer ................................................................................................................... 1-14AV-1 cylinder .......................................................................................................................... 7-7Axial alignment of condenser lens........................................................................................... 8-7Axial alignment of electron gun ............................................................................................... 8-6Axial alignment of electron optics............................................................................................ 8-5Axial alignment of objective movable aperture ........................................................................ 8-7Axial alignment of stigmator coil.............................................................................................. 8-9

BBeam controller screen ........................................................................................................... 8-8Brightness............................................................................................................... 2-3, 2-5, 8-12

CChip number ........................................................................................................................... 6-2Consumables........................................................................................................................ 10-1Contrast .................................................................................................................. 2-3, 2-5, 8-12CPU........................................................................................................................................ 4-1

DDaily check list ...................................................................................................................... 10-8Display unit ........................................................................................................................... 2-20

Control panel.................................................................................................................. 2-23Power supply switch....................................................................................................... 2-20Electron gun high voltage power supply......................................................................... 2-22Printer ............................................................................................................................ 2-24

I - 2

INDEX (cont’d)

EEvacuation control panel......................................................................................................... 2-9Evacuation control unit............................................................................................................ 4-1Evacuation system abnormalities............................................................................................ 9-3Evacuation system arrangement............................................................................................. 2-8EWS ....................................................................................................................................... 4-1External electric field noise ..................................................................................................... 1-4External power noise .............................................................................................................. 1-4

FFCM........................................................................................................................................ 3-3

GGas source ............................................................................................................................. 1-3GUI .................................................................................................................................. 2-3, 2-5

HHV control unit ........................................................................................................................ 4-1HV Setup Screen .................................................................................................................... 8-4

IImage Operation screen ......................................................................................................... 8-2Image processing unit............................................................................................................. 4-1Installation layout ............................................................................................................. 1-8, 1-9Installation requirements......................................................................................................... 1-1

LLine power requirements ........................................................................................................ 1-2Log data.................................................................................................................................. 9-9

I - 3

INDEX (cont’d)

MMain column unit.............................................................................................................. 2-4, 2-6Map operation......................................................................................................................... 6-7

OObjective movable aperture .................................................................................................... 8-5OFS control unit ...................................................................................................................... 4-1On-chip coordinates................................................................................................................ 6-2Optical microscope ................................................................................................................. 8-1

PPeriodic inspection................................................................................................................ 10-3

Objective movable aperture ........................................................................................... 10-5Evacuation system......................................................................................................... 10-4

Periodic check list ................................................................................................................. 10-9

RPower capacitance................................................................................................................ 1-10Retarding ................................................................................................................................ 3-2Rotary vacuum pump...........................................................................................................10-11

SSchottky Emission................................................................................................................... 3-1SE electron source.................................................................................................................. 3-1SEM condition memory......................................................................................................... 8-12SEM controller ........................................................................................................................ 4-1Shutdown of instrument .......................................................................................................... 7-6Software error ......................................................................................................................... 9-8Spare parts ........................................................................................................................... 10-2Specifications.......................................................................................................................... 2-2Stage control unit .................................................................................................................... 4-1Stage controller....................................................................................................................... 6-6Stage coordinate scheme ....................................................................................................... 6-1Stage/Evacuation control (manual) Panel ............................................................................. 2-14Stray magnetic field ................................................................................................................ 1-3System configuration .............................................................................................................. 4-1System files ............................................................................................................................ 5-1

I - 4

INDEX (cont’d)

TTroubleshooting ...................................................................................................................10-14Two-stage detection system ................................................................................................... 3-4

UUser files................................................................................................................................. 5-2

WWafer alignment ..................................................................................................................... 6-4Wafer coordinates .................................................................................................................. 6-3Wafer transfer controller ......................................................................................................... 9-4Wiring diagram ............................................................................................................ 1-15, 1-16WT control unit ....................................................................................................................... 4-1