decade of pulsed power development presentation
TRANSCRIPT
6/3/2004© Copyright 2004 Cymer, Inc.
A Decade of Solid State Pulsed Power Development at CYMER Inc.
R. Ness, P. Melcher, G. Ferguson, and C. HuangCYMER Inc., 17075 Thornmint Court,
San Diego, CA, 92127, USA2004 Power Modulator Conference, May 23-26, 2004
26/3/2004© Copyright 2004 Cymer, Inc.
Outline
h Background and History of Cymerh Pulse power requirements for lithography light-sourcesh High volume manufacturing requirements issuesh Survey of Cymer’s solid state pulse power
h Past, present and futureh Specificationsh Designh Lessons learned
36/3/2004© Copyright 2004 Cymer, Inc.
CYMER Background and History
h World's Leading Supplier of Excimer Lasers for Semiconductor Photolithography
h Founded in 1986 and Headquartered in San Diego, CA with ~800 Current Worldwide Employees
h Primary Customers are ASML, Nikon, and Canon but Lasers are Utilized in Virtually Every Semiconductor Fab (Fabrication) Facility
h 2282 CYMER Lasers Installed Worldwide as of Q1 2004 (Virtually All with Solid State Pulsed Power)
46/3/2004© Copyright 2004 Cymer, Inc.
Solid State Pulsed Power Module (SSPPM) Technology Introduced at CYMER in Early '90sh Components developed by Dan Birx Through a DARPA SBIR
Contracth Significant Advantages for Lithography Laser Over Prior
Technologyh "Infinite" Lifetime Compared to Thyratron Based Unitsh Energy Recovery of Pulse Reflected from Laser Load Increases Chamber
Lifetime Significantly (at Least ~70%)h Less Impact on Semiconductor Fab Operation (Fewer
Repairs/Replacements, No Warm-up Time Needed, etc.)h No Pre-Fires Causing Missing Pulses and Wafer Level Rework h Laser Cost of Ownership (CoO) Therefore Significantly Reduced
h First SSPPM Unit Shipped in Production Laser in 1995h ~3800 SSPPM Module Sets Manufactured Since Then
56/3/2004© Copyright 2004 Cymer, Inc.
Laser Trend is Higher Rep-Rate and Power, Lower Bandwidth, Lower Cost of Operation
SSPPM Introduced Here
Lithography Lasers Highly Line Narrowed (Lots of Energy Thrown Away for Spectral Purity).Therefore, Electrical Power Increases With Bandwidth Improvements in Addition to Rep-Rate Increases.
Example at Left is KrF TrendCoc/Bp: Cost of Consumables ($) / Billion Pulses
Spectral Power: Laser Power (W) / Laser Bandwidth (pm)
66/3/2004© Copyright 2004 Cymer, Inc.
Timeline History of Laser Model / SSPPM Generation Also Shows SSPPM Trends
Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
Laser ELS-4000F ELS-5000 ELS-5000A ELS-5010 ELS-6010 ELS-7000 ELS-7010Series KrF KrF ArF KrF KrF KrF KrFIntro EX-4000FA ELS-6000 ELS-6010A XLA100
ArF KrF ArF ArFNanoLith 7000
ArF
SSPPM 5000 5000 5010 6000 6010 7000 7000 XLA XLA EUVGeneration
Repetition 600 Hz 1000 Hz 1000 Hz 2000 Hz 2500 Hz 4000 Hz 4000 Hz 4000 Hz 4000 Hz 5000 HzRate
Output ~19 kV ~19 kV ~19 kV ~23 kV ~23 kV ~31 kV ~31 kV ~31 kV ~31 kV ~5 kVVoltage
Output 150 ns 150 ns 110 ns 100 ns 100 ns 60 ns 60 ns 60 ns 60 ns 30 nsRisetime
Higher Rep-Rate - More Laser Power and Higher Wafer ThroughputHigher Output Voltage - Typically More Laser Energy / Pulse and/or Tighter BW
Faster Output Risetime - Typically Better Energy Conversion
76/3/2004© Copyright 2004 Cymer, Inc.
A Variety of Issues Existed for Successful Volume Manufacturing of SSPPM Modulesh Design/Change Management: Detailed Documentation was
Developed:h Part Specificationsh Piece Part, Sub-Assembly, and Assembly Drawingsh Multi-Level Bills of Material (~800 Line Items)h Assy and Test Procedures for Sub-Assy and Module Levels
h Supply Chain: Procurement Had to Ramp Up With Parts / New Vendors
h Manufacturing/QA: Manufacturing Staff was Trainedh Testing: Intermediate and Final Test Stand HW was Set Uph Logistics: Worldwide Spares Distribution / Stocking was Initiated
86/3/2004© Copyright 2004 Cymer, Inc.
Semiconductor Fab Application Requires Very Long Lifetime / High Reliability
h ~5 Year Life on Fab Tool Implies Infinite SSPPM Lifetime (at Least 25 to 50B shots)
h Laser Demonstrates > 99% Total Uptimeh 5000 Series SSPPM Tested for Over 50B Shots
(Over 2.5 Years) With No Signs of Degradationh HALT Testing (Primarily Thermal) Conducted for
Multiple Generationsh Extensive Thermal Testing Done Prior to Design
Release
96/3/2004© Copyright 2004 Cymer, Inc.
5000 Series SSPPM Transfer Function Shows No Measurable Change After 50B Shots*
* IEEE PPC Melcher, Ness, et al. June 2001
Data Overlays WithinExperimental MeasurementAccuracy of ~5%
106/3/2004© Copyright 2004 Cymer, Inc.
5000 Series SSPPM Thermal HALT TestingNo Failures Up to 86 Deg. C Exhaust Air
20 30 40 50 60 70 80 90 10020
30
40
50
60
70
80
90
100
110
120
L SCR Heat Sink R SCR Heat Sink Bias Inductor Front ER Inductor Back ER Inductor Charge Inductor
Sens
or T
empe
ratu
re (D
eg. C
)
Bulk Exhaust Temperature (Deg. C)
116/3/2004© Copyright 2004 Cymer, Inc.
SSPPM Operating Voltage Range is Large Compared to Many Magnetic Pulse Compressors
h Laser Operating Voltage Varies Significantly Depending Upon Chamber Life and Gas Conditions
h Typical Range of Laser SSPPM Initial Stored Energy is ~1.5 to 5.5 J per Pulse
h Complicates SSPPM Magnetic Switch Designh Timing Compensation Required for Consistent
Propagation Delay Over Entire Voltage Range
126/3/2004© Copyright 2004 Cymer, Inc.
Many Other Issues are Also Important For This Application in Semiconductor Fab
h Packaging: Module Size Minimized Since Fab Floor Space is Very Expensive
h Serviceability: Weight and Ease of Troubleshooting Relate to Potential Field Service and Module Replacement
h Cost: Driving Factor Since it Impacts Profith Compliance: Need to Avoid Potential Fab Contaminants
h Minimize Fluid Impregnants Typically Used for HV Insulationh Use Materials Approved for Fab Use
h Safety: Units Must Also Comply With SEMI, UL, TUV Standards
136/3/2004© Copyright 2004 Cymer, Inc.
5000/5010 SSPPM System Requirements
h 1000 Hz Operationh 1.5 - 4.0 J/Pulse Initial Stored Energy on C0h 550 - 800 V Input Voltage Rangeh ~12 - 19 kV Output Voltage Rangeh 150 ns Output Voltage Risetime (5000)h 110 ns Output Voltage Risetime (5010)
146/3/2004© Copyright 2004 Cymer, Inc.
5000/5010 Series SSPPMElectrical Schematic Diagram
Compression HeadCommutator
HVPS
Laser Chamberh Capacitor Charging Power Supplyh Parallel SCR Switchingh 26X (28X in 5010) Inductive Voltage Adder Transformerh 3 Stages of Magnetic Pulse Compression
h 10 µs Initial Transfer Down to 150 ns
156/3/2004© Copyright 2004 Cymer, Inc.
5000 Series Laser Frame ShowingLocation of SSPPM Modules
(Behind Panel)
1000 V,6 kJ/sec
HVPS
Air-CooledCommutator
w 1st Compression
Stage and Pulse XFMR
Laser Controller
2 Stage,H20-CooledCompressionHead
Laser Chamber
166/3/2004© Copyright 2004 Cymer, Inc.
5000 Issues - Minor Problems Resolved During Initial Manufacturing and Production
h Magnetic Core Production Issuesh Instituted Close Monitoring of Magnetic Core Parameters
to Avoid Unacceptable Componentsh Compression Head Cooling
h Added Cold Plate to CH Housing to Cool Switch Cores and Minimize Loss of ∆B Due to Temp
h HV Cable Connector Problemsh Identified Errors in Commercial Connector Design
176/3/2004© Copyright 2004 Cymer, Inc.
5000 Timing Compensation - Customer Requires Tight Control of Throughput Delay*
h Stepper/Scanner Manufacturers Require Sync Out Signal for Their Own Diagnostics
h Trigger-to-Laser Light Must be Constant in Spite of SSPPM Operation at Different Voltages as Laser Chamber Ages
h Solution: Sample Final Charging Voltage and Insert Appropriate Proportional Delay in Low Level Electronics Prior to SCR Trigger
"Timing Compensation for an Excimer Laser Solid-State Pulsed Power Module (SSPPM)", with D. Johns, et al, IEEE Transactions on Plasma Science, Volume 28, Number 5, October 2000.
186/3/2004© Copyright 2004 Cymer, Inc.
6000/6010 SSPPM System Requirements
h 2000 Hz Operation (6000)h 2500 Hz Operation (6010)h 1.5 - 5.4 J/Pulse Initial Stored Energy on C0h 600 - 1150 V Input Voltage Rangeh ~12 - 23 kV Output Voltage Rangeh 100 ns Output Voltage Risetime
196/3/2004© Copyright 2004 Cymer, Inc.
6000/6010 Series SSPPMElectrical Schematic Diagram
Commutator Compression Head Laser ChamberHVPS
h Capacitor Charging Power Supplyh Parallel IGBT Switchingh 23X Inductive Voltage Adder Transformerh 2 Stages of Magnetic Pulse Compression
h 5 µs Initial Transfer Down to 100 ns
206/3/2004© Copyright 2004 Cymer, Inc.
6000 Series Laser Frame ShowingLocation of SSPPM Modules
(Behind Panel)
1200 V, 14 kJ/sec,Air-Cooled HVPS
Air-CooledCommutator
w 1st CompressionStage and
Pulse XFMR
Laser Controller
Air-Cooled,Single Stage CompressionHead
Laser Chamber
216/3/2004© Copyright 2004 Cymer, Inc.
6000 Series SSPPM Uses 2 Stages of Magnetic Pulse Compression (MPC) Vs. Prior 3 Stage Design
h Maturity of IGBT Technology Allowed Replacement of SCR and Enabled Faster Commutation Time (C0-C1 Transfer)
h Faster Commutation Time and Improvement to MPC Designs Allowed Elimination of One Stage of Pulse Compression
h Advantages:h Improved SSPPM Efficiencyh Better Residual Voltage Snubbingh Improved Manufacturability and Serviceability
226/3/2004© Copyright 2004 Cymer, Inc.
6000 UL/TUV ComplianceTesting Performed at CYMER
h Module Level Certification by NRTLs (Nationally Recognized Testing Labs)
h Tested to UL 3101-1 and EN 61010-1 Standardsh Includes Detailed Analysis of:
h Construction (Creepage and Clearance)h Material (Flammability, Electrical Properties, etc.)h Environmentalh Failure Modes
h Single-Point Failureh Fault Handlingh Electrical and Thermal
h Isolation and Grounding
236/3/2004© Copyright 2004 Cymer, Inc.
6000 Air/Water Heat Exchanger
h Environmental Control Important to Long-Term Reliability of Module
h Internal and External Resistance to Direct Water Cooling
h Compromise w/ Air-to-Water HXh Advantages:
h Ability to Control Critical Componentsh Reduced Need to Cooling Fluid Bathh Minimize Heat Load to Fab Air Exhaust
246/3/2004© Copyright 2004 Cymer, Inc.
6000 Timing Comp Improved From Single to Multi-Segment Linear Approximation
600 700 800 900 1000 1100 120030.14
30.15
30.16
30.17
30.18
30.19
30.20
30.21
30.22
30.23
30.24 T0+15 min T0+30 min T0+60 min T0+75 min T0+105 min
SSPP
M P
ropa
gatio
n D
elay
(µs)
Voltage (V)
Improved From Approximately + 200 ns to < + 50 ns Over Full Voltage Rangeand Operating Temperature Range as Module Heats Up with Time
256/3/2004© Copyright 2004 Cymer, Inc.
7000/7010 SSPPM System Requirements
h 4000 Hz Operationh 1.5 - 5.4 J/Pulse Initial Stored Energy on C0h 750 - 1450 V Input Voltage Rangeh ~16 - 31 kV Output Voltage Rangeh 60 ns Output Voltage Risetime
266/3/2004© Copyright 2004 Cymer, Inc.
7000/7010 Series SSPPMElectrical Schematic Diagram
HVPS Resonant Charger Commutator Laser ChamberCompHead
h Resonant Charging Power Supplyh Parallel IGBT Switchingh 25X Inductive Voltage Adder Transformerh 2 Stages of Magnetic Pulse Compression
h 4 µs Initial Transfer Down to 60 ns
276/3/2004© Copyright 2004 Cymer, Inc.
7000 Series Laser Frame ShowingLocation of SSPPM Modules
H20-Cooled, 30 kW, 800 V HVPS
H20-Cooled, 1450 VResonant Charger
H20-CooledCommutator w 1st
Compression Stage and Pulse XFMR
Laser Controller
H20-Cooled, Single Stage Compression Head
Laser Chamber
286/3/2004© Copyright 2004 Cymer, Inc.
Resonant Charger Technology Replaced Cap Charging Power Supply for 7000 Series SSPPM
h As Rep-Rate Increases, Inter-Pulse Time Decreasesh Significant Part of Time Required by Controller to
Calculate Voltage for Next Pulse in Constant Energy Modeh Additional Time Required for Energy Recoveryh As a Result, Time Allowed for Charging Decreasing Faster
Than Rep-Rate Increase - Cap Charger Not Effectiveh Solution - Resonant Charging and Simpler HVPS
h Pulse Charging can be Done Very Fasth HVPS Can Still Deliver Constant Power Flow to Filter Capacitor
Resulting in More Constant AC Power Draw with Fewer Harmonics
296/3/2004© Copyright 2004 Cymer, Inc.
Water Cooling Implemented for 7000 Series SSPPM Thermal Management
h Water Cooling Required to Remove Thermal Heat Loadh Implementation Features
h Cold Plate in Commutator for Cooling Semiconductors and 1st Stage Reactor Housing
h Water Tubing Supplied to Cool Output Reactor Housingh Inductive Isolation of High Voltage Potential
h No Joints Internal to Moduleh No Possibility of Leaks Inside Module
306/3/2004© Copyright 2004 Cymer, Inc.
Cooling Water Tubing to Output Magnetic Switch Housing Inductively Isolated
Solid Tubing Run Inside Chassis Avoids Joints and Leak PotentialCopper Tubing Also Provides Bias Current Return Path
316/3/2004© Copyright 2004 Cymer, Inc.
Laser Design Paradigm Occurs in 2002 at CYMER as Laser Power and BW Requirements Get Tougher
h Laser Power Traditionally Increased by Rep-Rate Increaseh However, Chamber Blower Power Increasing with Cube of
Rep-Rate (All Else Constant)h Chamber Acoustics and Tougher BW Complicating Issuesh Optics Issues and Module Lifetimes Also Not Acceptableh Solution - Two Chamber MOPA Laser
h Low Power Master Oscillator (MO) Which Produces Tight BWh High Gain Power Amplifier (PA) Which Boosts Output Power
326/3/2004© Copyright 2004 Cymer, Inc.
XLA Series Lasers Require Two Parallel SSPPM Systems to Drive MOPA Laser Configuration
h Laser Output Efficiency Strongly Dependent Upon MOPA Timing Synchronization
h PA SSPPM Output Pulse Must be Generated ~40 + 5ns After MO SSPPM Pulse so that PA is Energized When MO Light Pulse Arrives20 30 40 50 60
6
7
8
9
10
Out
put E
nerg
y (m
J)
MO-PA Delay (ns)
Operating Point
336/3/2004© Copyright 2004 Cymer, Inc.
XLA Series Laser Frame ShowingLocation of SSPPM Modules
MO Commutator
Resonant Charger
PA Commutator
MO Compression Head
MO Laser Chamber
PA Compression Head
PA Laser Chamber
HVPS
346/3/2004© Copyright 2004 Cymer, Inc.
XLA SSPPM Electrical Schematic Diagram
HVPS Resonant Charger Commutators CompHeads
LaserChambers
Common Resonant Charger Drives 2 Parallel SSPPMs for Master Oscillator and Power Amplifier
356/3/2004© Copyright 2004 Cymer, Inc.
IGBT Gate Driver Improvements Reduced Jitter From ~50 ns to Less Than 1 ns
AfterBefore
Commercial IGBT Driver Circuit Displayed Strong Delay vs. Rep-Rate Dependence and Strong Delay Drift Vs. Temperature
366/3/2004© Copyright 2004 Cymer, Inc.
A Magnetic Core Tester Was Developed to Confirm Switch Vsec Matching
HVPS
Pulser
Test Fixture
DataAcquisition System
Matching Helps Ensure MO-PA Synchronization Over All Voltages / Temperatures
376/3/2004© Copyright 2004 Cymer, Inc.
Cores Are Procured in Matched SetsWithin Range of Target Bsat
V*t=0.18838+0.81162*Bm(Correlation Coefficient R=0.92)
Nor
mal
ized
Vol
t-sec
ond
of R
eact
or
Normalized Average Bm of Magnetic Cores
386/3/2004© Copyright 2004 Cymer, Inc.
Kaiser Systems Resonant Charger Pulse-to-Pulse Regulation Difference Between Max-Min Out of 10 Bursts
111
2131
4151
6171
8191
750
850
950
1050
1150
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
MAX-MIN (%
PULSE COUNT
VOLTAGE
S/N 710018 SPREAD BY PULSE
396/3/2004© Copyright 2004 Cymer, Inc.
XLA Timing Synchronization Held to Less Than + 2.0 ns Between MO and PA SSPPMs
0
0.5
1
P uls e Inde x∆t M
OPA
Erro
r, ns
, σ
S igm a
0 10 20P roba bility, %
0 50 100 150 200 250-2.5
-2
-1.5
-1
-0.5
0
0.5
1
1.5
2
∆t M
OPA
Erro
r, ns
Cha m be r S ync h E rror, Ine rna l Ene rgy Control, 4 kHz
Ave ra geMinMa x
Laser Controller Handles Long Term Timing Changes Due to Thermal Drift and/or Voltage Changes
406/3/2004© Copyright 2004 Cymer, Inc.
SSPPM Systems Also Being Developed to Support EUV Lithography Light Sources
Electrodes
Insulator
Pinch
h Dense Plasma Focus Device Produces 13.5 nm Lighth SSPPM Design Conceptually Very Similar to Laser Designs
h Energy Recovery to Reduce Electrode Erosion / Improve Efficiencyh HV Power Supply and Resonant Chargingh Parallel IGBTs and Several Stages Magnetic Pulse Compressionh Inductive Voltage Adder Transformer
416/3/2004© Copyright 2004 Cymer, Inc.
EUV DPF SSPPM Requirements
h 5000 Hz Operationh 15 - 21 J/Pulse Initial Stored Energy on C0h 1200 - 1400 V Input Voltage Rangeh 4 - 5 kV Output Voltage Rangeh ~30 ns Output Voltage Risetime into DPF Load
426/3/2004© Copyright 2004 Cymer, Inc.
EUV DPF SSPPMElectrical Schematic Diagram
h Resonant Charging Power Supplyh Parallel IGBT Switchingh 4X Inductive Voltage Adder Transformerh 2 Stages of Magnetic Pulse Compression
h 4 µs Initial Transfer Down to ~30 ns Risetime on DPF Load
HVPS Resonant Charger SSPPM DPF Load
436/3/2004© Copyright 2004 Cymer, Inc.
Typical EUV DPF Output Waveforms Show Normal Pulse and Energy Recovery
-100 -50 0 50 100 150 200 250 300 350-3
-2
-1
0
1
2
3
4
5
6
Time (ns)
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Volta
ge (k
V)EU
V Emission (N
ormalized)
12.8J Input
2.7J Recovered
BLACK: C2 VoltageRED: Anode VoltageBLUE: EUV Emission
446/3/2004© Copyright 2004 Cymer, Inc.
EUV DPF SSPPM is Designed into aSingle, Coaxial Module
Magnetic Switch Bias Circuitry
Series Diodes andTriggers/Snubbers
IGBT DeckC0 Capacitor DeckC1 Capacitor Deck
Pulse Transformer
C2 Capacitor Decks (3)
456/3/2004© Copyright 2004 Cymer, Inc.
Thermal Management Design is Critical at ~100 kW Average Power Levels
h Water-Cooled Cold Plates Designed for Semiconductors (IGBTs and Series Diodes)
h Mandrel and Housing Hardware Also Developed to Remove Heat from Magnetic Coresh Integral Water Cooling Channels
h LS1 Charging Inductor or "Saturable Assist"h LS2 Magnetic Switchh Pulse Transformer Coresh LS3 (Output) Magnetic Switch
466/3/2004© Copyright 2004 Cymer, Inc.
EUV DPF Output Magnetic Switch Peak Temperature Reduced by ~Half
Fin
Magnetic CoreCore Mandrel
O.D.I.D.
Peak Temperature = ~160 Deg. CPeak Temperature = ~320 Deg. C
Baseline Design with Single 1.0" Core and Water Cooling to Core Mandrel
New Design with Water Cooling and 0.060" Fin Inserted Between Two 0.5" Cores and Improved Thermal Contact Between Core/Mandrel
476/3/2004© Copyright 2004 Cymer, Inc.
Future Development - Expected Trends
h Lasers and EUV Light Sources Will Continue to Require Higher Average Power and Higher Rep-Rates (Potentially up to 10 kHz)
h Higher (>30 kV) Output Voltages Likely Necessaryh Thermal Management Will Become Even More
Critical and More Complicatedh All Other Requirements Maintained (if Not Improved)
h Reliability and Lifetimeh Costh Packaging and Serviceabilityh Compliance and Safety
486/3/2004© Copyright 2004 Cymer, Inc.
Summary
h Commercial Pulsed Power Applications Do Exist!!h Pulsed Power Hardware Can be Reliableh Pulsed Power Hardware Can Have a Long
Lifetime (10's to 100's of B of Shots)
496/3/2004© Copyright 2004 Cymer, Inc.
Acknowledgements
h The Authors Would Like to Acknowledge:h Dan Birx for Transferring the SSPPM Technology to CYMER
(and Training us Well Enough to Carry On)h Brett Smith, Robert Saethre, and David Johns for
Engineering Various Designsh Bill Partlo for Guiding SSPPM Development Towards
Designs Optimized for Laser and Light Source Performanceh Terry Houston for Assembling, Modifying, Troubleshooting,
and Testing All of the Prototype Modulesh Kaiser Systems and Universal Voltronics for Developing
Power Supply and Charging Modules