Step-and-Repeat System

NSR-2205i14E (6" Reticle Type)

ACCEPTANCE TEST

Nikon Precision Inc.

January 9, 1998 JCW 1/98

22i14EAT01

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NSR-2205i14E ACCEPTANCE TEST ITEMS

(6" Reticle Type)

No. Item Specification Condition

1

Resolution

0.35µm or less

High resolution, positive resist film of 1.0µm thickness

2

Focus Calibration Repeatability

Within 80nm (3σ)

20 measurements

3

Lens Distortion (including magnification error)

Within ± 30nm

37 points / chip

4

Magnification Control

Within ± 15nm

3 measurements of Initial, Heat (150min.) and Cool (180min.)

5

Maximum Exposure Area

Within 31.11mm dia. 22.0mm x 22.0mm to 17.96mm x 25.2mm (horz.) (vert.)

6

Reticle Blind Setting Accuracy

+ 0.4 to + 0.8mm (on reticle)

7

Exposure Power

1100 mW/cm2 or more

Measured after a new lamp is installed

8

Integrated Exposure Stability (including integrated exposure matching)

Within ± 1.0% (75 mJ/cm2 or more) Within ± 0.5% (at 100mJ/cm2)

Input Exposure Time: 150, 200, 400, 800 msec.

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No. Item Specification Condition

9

Illumination Uniformity

Within ± 1.0%

Inside exposure area 5 measurements

10

Reticle Rotation

| M | + 3σ ≤15nm

Center of RR target value

11

Alignment Accuracy (FIA, LSA and LIA)

| M | + 3σ ≤ 40nm Center only | M | + 3σ ≤ 50nm Center and 4 corners

Resist on image EGA 8 point sampling

12

Array Orthogonality

Within ± 0.1 sec

After compensation with software Average of 3 wafers

13

Stepping Precision

3σ ≤ 30nm

Measurements from 2 wafers

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Wafer Prealignment repeatability

3σ ≤15µm

For each X, Y and θ axis 60 measurements / 1 wafer

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Throughput FIA-EGA LSA-EGA LIA-EGA*

120 wph (150 mm) 87 wph (200 mm) 108 wph (150 mm) 80 wph (200 mm) 103 wph (150 mm) 77 wph (200 mm)

2nd print, EGA 8 points sampling 150 mm wafer size: 32 shots 200 mm wafer size: 60 shots Step pitch 22mm x 22mm Exposure time = 0.082 sec

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No. Item Specification Condition

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Operational Test 1) Wafer transfer

system 2) Reticle transfer

system

1) success rate: 100% 2) success rate: 100%

1) Consecutive printing of 100

wafers, 2nd print 2) Excute a reticle change once for

each slot

17

Leveling Accuracy

Within ± 1.5 sec

On lens image plane 10 measurements

18

Leveling Repeatability

Within ± 1.0 sec

10 measurements

Note: Item * marked is option. MES (Measurement & Evaluation System) is used for measurement. Nikon Recommended Conditions for MES: Resist type: High resolution, positive resist. Resist thickness: 1.20 µm thickness

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NSR-2205i14E ACCEPTANCE TEST METHODS AND CONDITIONS

(6" Reticle Type)

Note: The Leveling system should be ON for test items listed in this acceptance test procedure. 0. Measurement Accuracy of NSR (MES usage condition)

0.1 The measurement accuracy of NSR shall be determined using “Measure (LSA or FIA).”

0.2 The photoresist specified by Nikon shall be used. The film thickness of the photoresist shall be 1.20µm. The followings are the guaranteed types of photoresist: i-line: THMR-iP1800 (Tokyo Ohka Kogyo) PFi-34 (Sumitomo Chemical) 0.3 Use of any other photoresist or conditions is subject to discussion between the

customer and NPI.

1. RESOLUTION

1.0 Illumination Condition: Lens NA = 0.63, σ = 0.60 1.1 Test Reticle: R2205HCD Ver. 4.09 or later Wafer: One bare silicon wafer 1.2 Exposure: Process Data: 22QIK5 Program Data: 22QIK5 Exposure Condition: Best exposure time Focus Pitch: 0.2µm 1.3 Photoresist: High resolution, positive resist film of 1.0µm thickness 1.4 Development: Tokyo Ohka NMD-3 (2.38%) 60 sec. Auto-puddle 1.5 Measurement: Optical microscope or SEM Linewidth: 0.35µm line and space V/H Evaluation Points: 5 points shown at Fig. 1.1.

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1.6 Judgment: Verify the 0.35µm line and space positive patterns are separated at all 5 points in the field for vertical and horizontal orientations at the best focus.

C (0,0)

UL (-10700, 10700)

LL (-10700, -10700)

UR (10700, 10700)

LR (10700, -10700)

Fig. 1.1

Resolution Evaluation Points 2. FOCUS CALIBRATION REPEATABILITY 2.1 Test Reticle: R2205HA Ver. 7.22 or later 2.2 Measurement: DIAGNOSIS, CALIBRATE command 2.3 Judgment: Take 20 measurements and calculate 3σn-1. 3. LENS DISTORTION (Including Magnification Error) 3.0 Illumination Condition: Lens NA = 0.63, σ = 0.60 3.1 Test Reticle: R2205HDIS Ver. 5.283 Wafer: Three Nikon Standard DIS bare silicon wafers

(for 6” wafer) One Nikon Standard DIS bare silicon wafer (for

8” wafer) 3.2 Exposure: Process Data: 22nMW Program Data: EXP Note: The letter n appearing in process data names denotes wafer size in inches.

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3.3 Measurement: Registration Metrology or FIA-AMS

(MEASURE command in the DIAGNOSIS group)

SMCP File: 22nDIS_FIA_2 (for distortion measurement) Evaluation Points: 37 points per chip shown at Fig. 3.1. 6" wafer : 33 shots (11 shots X 3 wafers) 8" wafer : 21 shots (21 shots X 1 wafer) 3.4 Calculation: Use distortion calculation command in the

Maintenance System V. 6" wafer : Average of 33 shots 8" wafer : Average of 21 shots Correct the Nikon Standard DIS-wafer error

data by using DISBSE conversion software in the Maintenance System V.

Convert the measured values in sign according

to each individual quadrant. Correct the reticle error. Compensate the reticle rotation error by

minimizing the rotation vectors of 37 points using the least squares method. Input the compensated value as a machine constant.

The final lens distortion data is the

measurement value at each field position minus the measurement value at the field center. The final distortion value at the field center will be zero.

3.5 Judgment: Evaluate the lens distortion in both X and Y

directions.

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Y

X 8mm 14mm 20mm 22mm 12X24mm

:DL :DR

Fig. 3.1

Measurement Points for Lens Distortion

4. MAGNIFICATION CONTROL 4.0 Illumination Condition: Lens NA = 0.63, σ = 0.60 4.1 Test Reticle: R2205HB Ver. 7.21 or later Wafer: Four bare silicon wafers 4.2 Exposure: Use LC Data Collection command in the

Maintenance System V. Process Data: 22nUSR2B Program Data: LCM Sequence: Shown at Fig. 4.1 Shutter open time = 1000 (msec) Shutter close time = 3.95 x Power - 1000

(msec) 4.3 Measurement: MEASURE command in the DIAGNOSIS

group SMCP File: 22nLCM_LSA_2 Evaluation Points: Measure the X component of vernier scale A

and the Y component of vernier scale B as shown in Fig. 4.2.

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Measurement points and number of wafers are as follows:

Measurement Wafer Size (mm) Points Per Wafer 150 26 200 35

Calculate the mean value of each axis.

Magnification errors are (Χ and Υ )/4. 4.4 Judgment: The magnification control is acceptable if the

magnification variations at the heat and cool times relative to the initial data are within specification.

Initial CoolHeat150 min 180 min

Open

Shutter closed

Fig. 4.1 Measurement Sequence of Magnification Control

B

A

Y

X

Fig. 4.2 Magnification Control Measurement Points

5. MAXIMUM EXPOSURE AREA

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5.0 Illumination Condition: Lens NA = 0.63, σ = 0.60 5.1 Test Reticle: R2205HB Ver. 7.21 or later Wafer: One bare silicon wafer 5.2 Exposure Process Data: 22nUSR2B Program Data: RB Exposure Condition: Best exposure time, best focus 5.3 Measurement: Optical microscope 5.4 Judgment: Verify that all portions on the outermost edges

of the test reticle are printed. 6. RETICLE BLIND SETTING ACCURACY

6.0 Use the wafer of item 5 - Maximum Exposure Area.

6.1 Measurement: Optical microscope Evaluation Points: Read the blind setting value from the position

scale as shown in Fig. 6.1. 6.2 Judgment: All scales should be printed within

specification.

2 1 0 1 2

Fig. 6.1

Reticle Blind Measurement Scale 7. EXPOSURE POWER

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7.0 Illumination Condition: Lens NA = 0.63, σ = 0.60 7.1 Power Meter: Nikon irradiance meter 7.2 Measurement: Integrated Exposure Stability measurement

command in the Maintenance System V Measure the exposure power after a new lamp

has been installed. 7.3 Judgment: The exposure power indicated on the Nikon

irradiance meter should be equal to or greater than the specification.

8. INTEGRATED EXPOSURE STABILITY 8.0 Illumination Condition: Lens NA = 0.63, σ = 0.60 8.1 Power Meter: Nikon irradiance meter 8.2 Measurement: Integrated Exposure Stability measurement

command in the Maintenance System V Exposure Power: 1 point with IDLE mode. Points: Use the average value of 5 points within the

shot (center and 4 corners of 10mm square). Input Shutter time: 150, 200, 400 and 800msec. 8.3 Judgment: Performance is acceptable when the difference

between the actual power exposure energy and the setting energy (input shutter open time X 500 mW/cm2) is within specification.

|Er - Ei| X 100 ≤ 1.0% (75 mJ/cm2 or more)

Ei ≤ 0.5% (100 mJ/cm2) Ei = input shutter open time X 500 mW/cm2 Er = actual exposure energy Note 1: 500 mW/cm2 is used as a standard exposure power for interchangeability

with conventional models. Note 2: Test condition - Actual exposure power should be 150 to 1100 mW/cm2.

The exposure energy should be 75 mJ/cm2 or more.

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Error

Theoretical Value

ure energy

Entered Shutter-open Time100 200 800

400

100

50

mj/cm2

msec

200

400

Fig. 8.1 Integrated Exposure Stability

9. ILLUMINATION UNIFORMITY 9.0 Illumination Condition: Lens NA = 0.63, σ = 0.60 9.1 Measurement: LAMP command in the DIAGNOSIS group Data File: 22LAMP_2 Number of measurements: 5 Wait at least 30 minutes after the lighting the

Hg lamp before taking measurement. 9.2 Judgment: All the measurement results should be within

specification. 10. RETICLE ROTATION 10.1 Test Reticle: R2205HDIS Ver. 5.283 Wafer: One bare silicon wafer

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10.2 Exposure Process Data: 22nUSR2D Program Data: RR1 to RR20 Expose wafers by using RR1 to RR20 without

unloading the wafer. Perform reticle alignment for every RR data

setting. Setting of SET system parameters in the SYSTEM group Reticle Driving Before Exposure: ON Reticle Driving During Shooting: ON Setting of EXECUTE exposure in the PROCESS group Reticle operation: Alignment only Wafer operation: Exposure only Carrier mode: Old 10.3 Measurement: MEASURE command in the DIAGNOSIS

group SMCP File: 22nRR20_LSA_2 Evaluation Points: 500 points (25 points/RR X 20 rows) Measure the Y components of the vernier

scales shown in Fig. 10.1 and Fig. 10.2. 10.4 Judgment: Evaluate reticle rotation as follows:

Reticle Rotation = M +3σn-1

M = (Σ Y i / 20) / 2 – (RE/2) – (RR target value) [i=1 to 20]

Y i : average of each RRi [i=1 to 20, n=25]

Re : Reticle Fabrication Error

RR target value: [DR(Y)–DL(Y)]/2

DR(Y) , DL(Y): Y vernier value shown as Fig. 3.1

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.

.

RR1

RR20

BL1 – BL20

BL3

BL19

BL20

BL1

BL2

BL18

Fig. 10.1

Reticle Rotation

RR1

RR2

RR19

RR20

.

.

.

.

Fig. 10.2

Reticle Rotation Within BL

11. ALIGNMENT ACCURACY 11.1 Test Reticle: R2205HA Ver. 7.22 or later Wafer: Ten bare silicon wafers / One sensor 11.2 Exposure

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Process Program Data: 22nUSR2A.REG1 (for first print) 22nUSR2A.FIA (for FIA second print) 22nUSR2A.EGA (for LSA second print) 22nUSR2A.LIA (for LIA second print) Wafer Alignment: Evaluate the overlay of resist images. Use LSA-EGA wafer alignment (8 EGA sample

points per wafer). Perform reticle alignment check and baseline

check for every 2 wafers. 11.3 Measurement: MEASURE command in the DIAGNOSIS

group SMCP File: 22nREG05_LSA_2 Evaluation Points: 1000 points (5 points/shot X 20 shots/wafer X 10 wafers) 11.4 Judgment: Evaluate alignment accuracy as follow : Alignment Accuracy = M + 3σn-1

n = 200 (center) n = 1000 (center and 4 corners) Evaluate the alignment accuracy in both X and

Y directions separately. 12. ARRAY ORTHOGONALITY 12.1 Test Reticle: R2205HB Ver. 7.21 or later Wafer: Three bare silicon wafers 12.2 Exposure Process Data: 22nUSR2B Program Data: ORT1 (for first print) 12.3 Measurement Process Data: 22nUSR2B Program Data: ORTM (for second 0° measurement) ORTM90 (for second 90° measurement) Measure the wafer by using FIA-EGA

measurement.

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12.4 Judgment: Evaluate array orthogonality as follows: After all necessary array orthogonality

corrections have been made through software, make final judgment based on the average of measurement values from 3 wafers.

Array Orthogonality = –(ORT0 + ORT90 )/2 ≤ 0.48 x 10-6 rad (= 0.1 sec) ORT0 : measurement result of ORTM ORT90 : measurement result of ORTM90 13. STEPPING PRECISION 13.1 Test Reticle: R2205HA Ver. 7.22 or later Wafer: Two bare silicon wafers 13.2 Exposure Process Data: 22nUSR2A Program Data: STEP 13.3 Measurement: MEASURE command in the DIAGNOSIS

group SMCP File: 22nSTEP_LSA_2 Evaluation Points: Measure the X component of vernier scale A

and the Y component of vernier scale B as shown in Fig. 4.2. Measurement points and number of wafers are as follows:

Measurement Wafer Size (mm) Points Per Wafer 150 26 200 35 13.4 Judgment: Calculate the 3σn-1 per each wafer. Evaluate the stepping precision in both X and

Y directions separately.

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14. WAFER PREALIGNMENT REPEATABILITY 14.1 Test Reticle: R2205HB Ver. 7.21 or later Wafer: One bare silicon wafer 14.2 Exposure Process Data: 22nUSR2B Program Data: ORT1 14.3 Measurement: Wafer Prealignment Repeatability

measurement command in the Maintenance System V

Process Data: 22nUSR2B Program Data: WLREP Number of Measurements: 60 14.4 Judgment: Calculate 3σ n-1 for X, Y and θ axes,

separately. 15. THROUGHPUT 15.1 Test Reticle: R2205HA Ver. 7.22 or later Wafer: 13 bare silicon wafers / One sensor 15.2 Exposure Process Program Data: 22nUSR2A.THRPT1 (for first print) 22nUSR2A.THRPTF (for FIA second print) 22nUSR2A.THRPTE (for LSA second print) 22nUSR2A.THRPTL (for LIA second print) Wafer Alignment: Evaluate the overlay of resist images. Use EGA wafer alignment (8 EGA sample

points per wafer). Exposure Time: 82 msec., timer mode 15.3 Measurement: Measure the time interval from the completion

of exposure of the first shot on the second wafer to the completion of exposure of the first shot on the 12th wafer.

15.4 Judgment: Calculate the throughput per hour by using the

results of item 15.3.

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16. OPERATIONAL TEST 16.1 Wafer Transfer System 16.1.1 Test Reticle: R2205HA Ver. 7.22 or later Wafer: 50 bare silicon wafers 16.1.2 Exposure Process Data 22nUSR2A Program Data: THRPT1 (for first print) Program Data: ALRUN (for second print) Second Print: Evaluate the overlay of resist images. Use LSA-EGA wafer alignment (3 EGA sample

points per wafer). Perform resist image 2nd print operation on

100 wafers consecutively(50 wafers X 2 times). 16.1.3 Judgment: No errors which cannot be recovered from

through software control are allowed. 16.2 Reticle Transfer System 16.2.1 Test Reticle: Any reticle 16.2.2 Execute the reticle change operation once for each slot. 16.2.3 Judgment: The transfer motion should be smooth and free

from stops due to errors. 17. CHIP LEVELING ACCURACY

17.0 Illumination Condition: Lens NA = 0.63, σ = 0.60

17.1 Image Plane Angle

17.1.1 Test reticle: R2205HMF Ver. 6 series or later Wafer: 1 bare silicon wafer

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17.1.2 Exposure Leveling Off. Process Program Data: 22MF096.INC09 Exposure Condition: Best exposure time Focus Pitch: 0.3µm 17.1.3 Photoresist: Positive photoresist, 1.2µm thick 17.1.4 Development: Tokyo Ohka NMD-3 (2.38%) 60 sec. Auto-

puddle 17.1.5 Measurement: MEASURE command in the DIAGNOSIS

group (Per MEASURE command operating

conditions) SMCP file: 22INCF09H Linewidth: 0.35µm line and space V/H Evaluation Points: 9 points shown at Fig. 17.1. (18 points total, vertical and horizontal

separately) 17.1.6 Image Plane Angle: Take best focus measurements for 9

evaluation points (18 points total, vertical and horizontal separately) and store the measurement data in a file.

Read the stored file by using a tool software

and obtain an estimate of wafer plane tilt (X, Y two directions).

This is the image plane angle (θx0, θY0).

LE

LRLCLL

UC URUL

CE RI

UR =UC =UL =LE =LL =LC =LR =

CE =

RI =

( 9700, 9700 ) ( 0, 9700 ) (-9700, 9700 ) (-9700, 0 ) (-9700, -9700 ) ( 0, -9700 )

( 9700, 0 )

( 0, 0 )

( 9700, -9700 )

5" Reticle, 20mm

( 10700, 10700 )( 0, 12000 )(-10700, 10700 )(-10700, 0 )(-10700, -10700 )( 0, -12000 )

( 10700, 0 )

6" Reticle, 22mm

( 10700, -10700 )

( 0, 0 )

Fig. 17.1 Image Plane Angle Evaluation Points

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θX0

θY0

Y0θθ X0

(deg)

Fig. 17.2 Image Plane Angle

17.2 Reference Leveled Wafer Plane

17.2.1 Wafer: Use a bare silicon wafer (without resist) with flatness within 2µm.

17.2.2 Measurement: FLATNESS command in the DIAGNOSIS

group Process Program Data: 22nLEVEL.LEVEL Map Size: 20 X 20 Step Pitch: 1000 X 1000 (µm) Wafer center leveling: ON Shot center leveling: OFF Ave. number: 20 Measurement number: 10 consecutive measurements without

unloading the wafer. Store each measurement result in the file.

17.2.3 Leveled wafer plane angle: Read the stored files by using the tool

software and determine the approximate image plane tilt (for both X and Y directions).

This is the leveled wafer plane angle (θXLi, θYLi).

17.2.4 Reference leveled wafer plane angle: Average the 10 measurements of the

leveled wafer plane angle. This is the reference leveled wafer plane angle (θXL, θYL).

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θXLi

YLiθ Leveled wafer plane angle :YLiθ

θ XLi

(deg)

Reference leveled wafer plane angle :

(deg) YLθ YLiθΣ= ( ) /10( i = 1 to 10)

θ XL θXLiΣ= ( ) /10

Fig. 17.3 Measurement of the leveled wafer plane angle

17.3 Judgment: Evaluate the difference between the image

plane angle (Item 17.1.6) and the reference leveled wafer plane angle (Item 17.2.4).

Evaluate θX, θY separately. θX : -1.5 ≤ (θXL - θX0) ≤ +1.5 θY : -1.5 ≤ (θYL - θY0) ≤ +1.5 (sec)

18. CHIP LEVELING REPEATABILITY

18.1 Use the reference leveled wafer plane angle and the leveled wafer plane

angle in Item 17.2. 18.2 Judgment: The machine performance is acceptable if the

maximum and minimum values of the leveled wafer plane angles θXLi and θYLi (i = 1 to 10) according to Item 17.2.3 do not differ by more than ±1.0 seconds from the reference leveled wafer plane angles θXL and θYL determined in Item 17.2.4.

Evaluate θX and θY separately. θX: -1.0 ≤ (Min. θXLi - θXL) +1.0 ≥ (Max. θXLi - θXL) θy: -1.0 ≤ (Min. θYLi - θYL) +1.0 ≥ (Max. θYLi - θYL) (i = 1 to 10)

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NSR-2205i14E ACCEPTANCE TEST RESULTS

(6" Reticle Type)

Serial No.:_______________ Acceptance Test Completion Date:______________ Inspected By:_____________________________ User's Machine ID:___________ No. Item Specification Result

1

Resolution

0.35µm or less

2

Focus Calibration Repeatability

Within 80nm (3σ)

3

Lens Distortion (including magnification error)

Within ± 30nm

4

Magnification Control

Within ± 15nm

5

Maximum Exposure Area

Within 31.11mm dia. 22.0mm x 22.0mm to 17.96mm x 25.2mm (hor.) (vert.)

6

Reticle Blind Setting Accuracy

+ 0.4 to + 0.8mm (on reticle)

7

Exposure Power

1100 mW/cm2 or more

8

Integrated Exposure Stability (including integrated exposure matching)

Within ± 1.0% (75 mJ/cm2 or more) Within ± 0.5% (at 100mJ/cm2)

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No. Item Specification Result

9

Illumination Uniformity

Within ± 1.0%

10

Reticle Rotation

| M | + 3σ ≤ 15nm

11

Alignment Accuracy (LSA, FIA, and LIA)

FIA-EGA | M | + 3σ ≤ 40nm Center only | M | + 3σ ≤ 50nm Center and 4 corners LSA-EGA | M | + 3σ ≤ 40nm Center only | M | + 3σ ≤ 50nm Center and 4 corners LIA-EGA* | M | + 3σ ≤ 40nm Center only | M | + 3σ ≤ 50nm Center and 4 corners

12

Array Orthogonality

Within ± 0.1 sec

13

Stepping Precision

3σ ≤ 30nm

14

Wafer Prealignment repeatability

3σ ≤ 15µm

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No. Item Specification Result

15

Throughput FIA-EGA LSA-EGA LIA-EGA

120 WPH (150mm) 87 WPH (200mm) 108 WPH (150mm) 80 WPH (200mm) 103 WPH (150mm) 77 WPH (200mm)

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Operational Test 1) Wafer transfer

system 2) Reticle transfer

system

1) success rate: 100% 2) success rate: 100%

17

Leveling Accuracy

Within ± 1.5 sec

18

Leveling Repeatability

Within ± 1.0 sec

Note: Item * marked is option. MES (Measurement & Evaluation System) is used for measurement. Nikon Recommended Conditions for MES: Resist type: High resolution, positive resist. Resist thickness: 1.20 µm thickness