euv source development in japankawatalab/workshop/aendo.pdffinal goal euv:115w 4 us-japan workshop...
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US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya1
EUV Source Development in JapanEUV Source Development in Japan
Akira Endo
Extreme Ultraviolet Lithography System Development Association (EUVA)
Hiratsuka R&D Center, 1200 Manda, Hiratsuka, 254-8567Japan
US-Japan Workshop on Heavy Ion FusionSeptember 28-30
Utsunomiya, Japan
AcknowledgementsThis work was supported by the New Energy and Industrial This work was supported by the New Energy and Industrial
Technology Development Organization (NEDO), Japan.Technology Development Organization (NEDO), Japan.
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya2
OutlineOutline
Back Ground and Development Roadmap Back Ground and Development Roadmap Choice of Driver Laser, Choice of Driver Laser, Nd:YAG / CONd:YAG / CO22 LaserLaser
Status of HighStatus of High--Power Nd:YAG Laser and Xenon JetPower Nd:YAG Laser and Xenon JetCost merit of Cost merit of COCO22 LaserLaser
EUV light source by COEUV light source by CO22 laser driven Xe droplets for HVMlaser driven Xe droplets for HVMCharacterization of COCharacterization of CO22 laser driven EUV Sourcelaser driven EUV SourceXe Droplet TargetXe Droplet TargetMagnetic Field Ion Mitigation Magnetic Field Ion Mitigation HighHigh--PowerPower COCO22 LaserLaser
SummarySummary
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya3
Laser Produced Plasma EUV Microlithography System
※LPP: Laser Produced Plasma
Driver Laser Intermediate Focus (IF)
Final GoalEUV:115W
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya4
Issues for EUV Source DevelopmentIssues for EUV Source Development
EUVL Light Source RequirementsEUVL Light Source Requirements (100 wafer/hr throughput, 300mm wafer)(100 wafer/hr throughput, 300mm wafer)
■■ 115W EUV in115W EUV in--band power (intermediate focus)band power (intermediate focus)■■ ±±0.3% energy stability (30.3% energy stability (3σσ, 50 pulses moving average), 50 pulses moving average)■■ Acceptable Initial cost and CoO Acceptable Initial cost and CoO
Issues of Source DevelopmentIssues of Source Development■■ High Conversion Efficiency (CE)High Conversion Efficiency (CE)
laser optimization, e.g. laser pulse energy & laser pulse widthlaser optimization, e.g. laser pulse energy & laser pulse width■■ High Repetition Rate Laser (>10kHz)High Repetition Rate Laser (>10kHz)
achieve EUV energy stability increasing the integral pulse numbeachieve EUV energy stability increasing the integral pulse numberr■■ Driver Laser Choice for Driver Laser Choice for Initial costInitial cost
introduction of industrial CO2 laserintroduction of industrial CO2 laser■■Mirror Lifetime Extension for CoOMirror Lifetime Extension for CoO
magnetic field ion mitigationmagnetic field ion mitigation
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya5
R&D Organization of EUV Light SourceR&D Organization of EUV Light Source
EUV Light Source Development Technical Committee・Chair : Koichi Toyoda (EUVA)・Vice-Chair: Kunioki Mima (Inst. of Laser Engineering Osaka Univ.)
Tokyo Instituteof Technology
Capillary discharge
EUVAEUVALight Source Development ProjectLight Source Development Project
High Power LPP System
HiratsukaResearch Center
Evaluation
Kumamoto University
Capillary discharge
MEXTMEXTLeading ProjectLeading Project
Osaka University
Plasma Simulation
MiyazakiUniversity
LPPUniversity of
HyogoSolid Xe Target
KyushuUniversity
LPPOther participants
Kyouto Univ., Okayama Univ., Yamanashi Univ., Nara Woman's College, Kitazato Univ., Nuclear Fusion Lab., Japan Atomic Energy Research Inst. Kansai、Inst. for Laser Science
Basic Technologies Basic Technologies
Collaboration
Sn TargetGotenba Branch Lab.High Power DPP System
R&D for Tool and SystemR&D for Tool and System
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya6
Key Technologies of EUVA LPP Light SourceKey Technologies of EUVA LPP Light Source
Target Technology- High velocity- High stability
Laser Technology- High power- Short Pulse duration
Chamber Technology- High vacuum- Small foot print- Heat management
Mirror Technology- Long lifetime- Large solid angle- High reflectivity
Xe JetXe Jet⇒⇒ Xe DropletsXe Droplets
YAG LaserYAG Laser⇒⇒ COCO22 LaserLaser
Mitigation by Mitigation by Magnetic FieldMagnetic Field
Xenon PlasmaXenon Plasma
Xe ReXe Re--circulationcirculation
LPP-EUV light source・High power/stability・Long lifetime・Low CoO
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya7
DPP source developmentDPP source development
Discharge Produced Plasma
Directly produced by discharge current.Controllable by discharge condition.
* Simple & compact source system* Flexibility as a light source
Pulse generator
ElectrodeElectrode
Insulator
EUV
Dischargegas
Key issues for DPP as a EUV source- Increase of EUV power at intermediate focus. - Debris mitigation & collector lifetime.- Electrode lifetime.
Key issues for DPP as a EUV source- Increase of EUV power at intermediate focus. - Debris mitigation & collector lifetime.- Electrode lifetime.
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya8
ZZ--pinch plasma for EUV radiationpinch plasma for EUV radiation
Cathode
Pinched plasma
Z-pinch plasma :
・Magnetic confinement・Dynamic plasma
Optimization for Lithography :
- Wavelength = 13.5nm- Small plasma size- Stable- High repetition rate- Clean- Long lifetime and CoO
Optimization for Lithography :
- Wavelength = 13.5nm- Small plasma size- Stable- High repetition rate- Clean- Long lifetime and CoO
Insulator Anode
Magnetic pressure
EUV
Magnetic field
Pulsed-power generator
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya9
LPP EUV Source RoadmapLPP EUV Source Roadmap
5.7W---
YAG:1.5kW10kHz0.9%
Xe-Jet
1st Mid term2004/9
115W3s<±0.3%CO2*: 60kW
100kHz0.7%
Xe-Droplet
HVM Source (2009)
10Ws<±10%
CO2*:6.8kW100kHz
0.5%Xe-Droplet
2nd Mid term2006/3
50Ws <±5%
CO2*: 30kW100kHz
0.6%Xe-Droplet
EUV Power (IF)StabilityLaser
Laser freq.CE (source)
Target
EUVA Final2008/3Item
with Pre-Pulse YAG Laser*Technology for 10WTechnology for 10WNd:YAG Laser, Liquid Xe jet
Technology for 115WTechnology for 115WCO2 Laser, droplet targetMagnetic field mitigation
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya10
OutlineOutline
Back Ground and Development RoadmapBack Ground and Development RoadmapChoice of Driver Laser, Choice of Driver Laser, Nd:YAG / CONd:YAG / CO22 LaserLaser
Status of HighStatus of High--Power Nd:YAG Laser and Xenon JetPower Nd:YAG Laser and Xenon JetCost merit of Cost merit of COCO22 LaserLaser
EUV light source by CO2 laser driven Xe droplets for HVMEUV light source by CO2 laser driven Xe droplets for HVMCharacterization of CO2 laser driven EUV SourceCharacterization of CO2 laser driven EUV SourceXe Droplet TargetXe Droplet TargetMagnetic Field Ion Mitigation Magnetic Field Ion Mitigation HighHigh--Power CO2 LaserPower CO2 Laser
SummarySummary
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya11
1.51.5--kW Nd:YAG Laser SystemkW Nd:YAG Laser System
Master OscillatorRep. rate: 10kHz
Pre Amp.
Main Amp.
Booster Amp.
Isolator
50W50W6.8ns6.8ns
415W415W6.3ns6.3ns
6W6W7ns7ns
[Description ]・Nd:YAG MOPA※ System・Output power:1500W・Repetition rate:10kHz・Pulse duration:6ns(FWHM)
※ MOPA : Master Oscillator and Power Amplifier
1000W
1000 W1000 W
1500W1500W500 W500 W
1000W
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya12
Xenon Jet TargetXenon Jet Target
Xenon Xenon JetJet
LaserLaser
3 mm
1 mm30m
m30
mm
Xenon jetXenon jet•• Jet diameter:Jet diameter: Approx. 50Approx. 50μμmm•• Jet speed:Jet speed: >35m/s>35m/s•• Jet stability:Jet stability: 9% (19% (1σσ))
@ 30mm from nozzle@ 30mm from nozzle
Behavior afterBehavior afterlaser irradiation laser irradiation (115mJ, 2Hz)(115mJ, 2Hz)
-- Break up length Break up length 1mm/pulse1mm/pulse-- Deformation length Deformation length 3mm/pulse3mm/pulse
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya13
EUV Output with 1.5EUV Output with 1.5--kW YAG Laser SystemkW YAG Laser System
•• EUV Power at Source: EUV Power at Source: 13.3W13.3W (2%BW/2(2%BW/2ππsr)sr)
at I.F.:at I.F.: 5.7W5.7W (Calculated)(Calculated)•• Conversion Efficiency:Conversion Efficiency: 0.9%0.9%•• EUV Energy Stability:EUV Energy Stability: 1.3% 1.3% (1(1σσ, 50, 50--pulse ave.)pulse ave.)
•• Laser Power: Laser Power: 1500W@10kHz, 6ns1500W@10kHz, 6ns•• Target: Target: Liquid Xenon jetLiquid Xenon jet
0.0
0.5
1.0
1.5
2.0
2.5
0 20 40 60 80 100 120 140 160 180 200
Number of pulses
In-b
and
EUV
ener
gy [m
J]
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya14
Cost estimation of LPP light sourceCost estimation of LPP light source
■■ Initial Cost Initial Cost :: 5.6~9.0 5.6~9.0 Mill.$ @ COMill.$ @ CO22,, 21.7~31.721.7~31.7 Mill. $ @ YAGMill. $ @ YAG
■■ Running CostRunning Cost:: 0.55~0.82 0.55~0.82 Mill.$/yearMill.$/year @ CO@ CO22,, 2.54~3.632.54~3.63 Mill.$/year @ YAGMill.$/year @ YAG
2.54~3.632.54~3.6321.7~31.721.7~31.70.55~0.820.55~0.825.6~9.05.6~9.0
YAGYAG(C.E.=1.2~0.8%)(C.E.=1.2~0.8%)
COCO22(C.E.=1.0~0.5%)(C.E.=1.0~0.5%)
110 JYen = 1 USD
0.20.20.50.51.01.0
20.0~30.020.0~30.0
Initial CostInitial Cost(M$)
0.06~0.220.06~0.220.140.140.030.03
0.32~0.430.32~0.43
Running CostRunning Cost(M$/year)
0.140.140.50.5Xe ReXe Re--Circulation SystemCirculation System
0.09~0.140.09~0.140.20.2Collector MirrorCollector Mirror
0.020.021.21.2EUV ChamberEUV Chamber
2.29~3.332.29~3.333.7~7.13.7~7.1Laser SystemLaser System
Running CostRunning Cost(M$/year)
Initial CostInitial Cost(M$)Total
Component
〈〈42~84kW,42~84kW, 100kHz 100kHz 〉〉
※※ Estimation based on:Estimation based on: -- 115W Source Power at I.F. 115W Source Power at I.F. -- 100 units produced in 2016.100 units produced in 2016.-- 120 wafer/hr throughput120 wafer/hr throughput ⇒⇒ 21.3 Billion pulse /year @ 10kHz21.3 Billion pulse /year @ 10kHz
⇒⇒ 213 Billion pulse /year @ 100kHz213 Billion pulse /year @ 100kHz
COCO22 Driver laser system for LPPDriver laser system for LPP
〈〈35~53kW,35~53kW, 10kHz 10kHz 〉〉
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya15
OutlineOutline
Back Ground and Development Roadmap Back Ground and Development Roadmap Choice of Driver Laser, Choice of Driver Laser, Nd:YAG / CONd:YAG / CO22 LaserLaser
Status of HighStatus of High--Power Nd:YAG Laser and Xenon JetPower Nd:YAG Laser and Xenon JetCost merit of Cost merit of COCO22 LaserLaser
EUV light source by COEUV light source by CO22 laser driven Xe droplets for HVMlaser driven Xe droplets for HVMCharacterization of COCharacterization of CO22 laser driven EUV Sourcelaser driven EUV SourceXe Droplet TargetXe Droplet TargetMagnetic Field Ion Mitigation Magnetic Field Ion Mitigation HighHigh--PowerPower COCO22 LaserLaser
SummarySummary
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya16
Light Source Concept for 115WLight Source Concept for 115W
Target Chamber
Beam splitter
Collector Mirror
Xe Droplet Target
EUV / 13.5nm
Magnetic Field Ion Mitigation
Bsub-ns Nd:YAG laser
(pre-pulse)
ns-order CO2 laser(main pulse)
Conversion Efficiency (CE) of 0.6% has been achieved (Xe Jet)
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya17
Characterization of preCharacterization of pre--pulsed CO2 Laser Plasma pulsed CO2 Laser Plasma
QCM
Camera
Photo Diode
TOF
EUV Energy Meter
Photo Diode
Xe Jet (30μm)Main Pulse Laser
〈CO2 Laser 〉Energy: 50 mJPulse Width: 25 nsIntensity: 6x109 W/cm2
Repetition rate: 10 Hz
Pre-Pulse Laser〈Nd:YAG Laser〉
Energy: 5 mJ, Pulse Width: 10 ns, Intensity: 8x109 W/cm2,Repetition rate: 10 Hz
1) EUV imageEtendue < 1mm2sr
2) plasma emissionin-band, out-of-band characteristics
3) Time of Flight (TOF)ion energy distribution with pre-pulse
4) Quartz Crystal Microbalance (QCM)mirror erosion rate (lifetime estimation)
Experimental Setup
Spectrograph
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya18
TEA CO2 Laser Driver System
3-Stage CO2 Laser System Configuration
Amplifier No1Amplifier No1 Amplifier No2Amplifier No2
OscillatorOscillator
10mJ 100mJ 300mJ
3Pass Amplifier
Oscillator Laser 25ns Pulse Duration
3Pass Amplifier
SpecificationsPulse Energy: 300 mJ, Pulse Duration: 25 nsRep. rate: 10 Hz
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya19
Conversion Efficiency of preConversion Efficiency of pre--pulsed CO2 laser Plasmapulsed CO2 laser Plasma
Pre-pulse laser increases CE significantly:
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.0E+00 1.0E+10 2.0E+10 3.0E+10 4.0E+10 5.0E+10 6.0E+10 7.0E+10
CO2 laser Power Intensity [W/cm2]
CE o
f CO
2 La
ser
LPP
with
Xe
Jet
15ns 25ns 45ns
Pre+15ns Pre+25ns Pre+45ns
Target
Max. CE = 0.6%
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya20
EUV in-band Plasma Image - delay time dependence -
5mJ Nd:YAG 50mJ CO2CO2 50mJ, 25ns, 6x10^9 W/cm2Nd:YAG, 5mJ, 8ns, 8x10^9 W/cm2
CCD
45 deg
Nd:YAG
CO2
Xe jet
Magnification:6.3
Pixel size:13μm
Mo/Si mirrorr=500mm
Xe jetXe jet
Nd:YAG +
CO2
delay:
600 ns
100 ns 200 ns50 ns
400 ns
0 ns
800 ns 1000 ns
250µm
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya21
CO2 Laser Plasma emissionCO2 Laser Plasma emission - delay time dependence -
Photo diode measurement: EUV (AXUV-100G+Zr filter)Out-of-Band (AXUV-100G + low-pass filter)
CO2 50mJ, 25ns, 6x10^9 W/cm2Nd:YAG, 5mJ, 8ns, 8x10^9 W/cm2Xe-jet, 30um diameter
0.00E+00
5.00E-09
1.00E-08
1.50E-08
2.00E-08
2.50E-08
0 0.2 0.4 0.6 0.8 1 1.2
delay(uS)
max
EU
V s
ignal
[a.
u.]
系列1
系列2
max. EUV emission (about 250μJ, 2Pi) at about 200ns
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
-0.5 0 0.5 1 1.5
delay from Yag [us]
energ
y [m
J]
200-370nm
370-520nm
520-720nm
in 2 π sr
energy emitted into 2π sr:EUV: 250uJ1.06um: 500uJ
With pre-pulseWithout pre-pulse
EUV Out-of-Band
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya22
Plasma emissionPlasma emission ((InIn--band, band, 1100 –– 2200nm nm ))
0nsdelay time: Nd:YAG -CO2
50ns
200ns
600ns
CO2 50mJ, 25ns, 6x10^9 W/cm2Nd:YAG, 5mJ, 8ns, 8x10^9 W/cm2Xe-jet, 30um diameter
Observed in-band emission at plasma source
wavelength (nm) wavelength (nm)
max. EUV emission at about 200ns delay time
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya23
Plasma emissionPlasma emission ((outout--ofof--band, 200band, 200--1700nm)1700nm)
CO2 50mJ, 25ns, 6x10^9 W/cm2Nd:YAG, 5mJ, 8ns, 8x10^9 W/cm2Delay time: 200nsXe-jet, 30um diameter
Observed out-of-band emission at plasma source
-1000
0
1000
2000
3000
4000
5000
6000
0 100 200 300 400 500 600
Pixec
Inte
nsi
ty1000 1200 1400 1600
wavelength (nm)-1000
0
1000
2000
3000
4000
5000
6000
0 100 200 300 400 500 600
Pixec
Inte
nsi
ty1000 1200 1400 1600
wavelength (nm)
900 – 1700nm
0
10
20
30
40
50
60
70
100 200 300 400 500 600 700 800 900
Wavelength (nm)
Inte
nsi
ty
200 – 850nm
Obtained out-of-band ratio from the spectrum was correspond with the result from photo diode measurement
900 – 1700nm: only Nd:YAG observed (10% scattered into 2π sr, 500µJ); CO2 wavelength range not yet measured
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya24
EUVリソの特徴- 露光波長が13.5nm- 反射光学系(含マスク)- 真空中で運転
0.0E+00
1.0E+09
2.0E+09
3.0E+09
4.0E+09
5.0E+09
6.0E+09
7.0E+09
0.E+00 2.E+03 4.E+03 6.E+03 8.E+03
Ion Energy (eV)
Ion D
istr
ibution (
arb
. unit)
0.0E+00
1.0E+09
2.0E+09
3.0E+09
4.0E+09
5.0E+09
6.0E+09
7.0E+09
0.E+00 2.E+03 4.E+03 6.E+03 8.E+03
Ion Energy (eV)
Ion D
istr
ibution
(arb
. unit)
Delay: 50ns Delay: 200ns
0.0E+00
1.0E+09
2.0E+09
3.0E+09
4.0E+09
5.0E+09
6.0E+09
7.0E+09
0.E+00 2.E+03 4.E+03 6.E+03 8.E+03
Ion Energy (eV)
Ion D
istr
ibution (
arb
. unit)
Pre pulse Nd:YAG only
0.0E+00
1.0E+09
2.0E+09
3.0E+09
4.0E+09
5.0E+09
6.0E+09
7.0E+09
0.E+00 2.E+03 4.E+03 6.E+03 8.E+03
Ion Energy (eV)
Ion D
istr
ibution
(ar
b. unit)
Delay: 0ns
Fast ion TOF measurement Pre-pulse (Nd:YAG 5mJ) + CO2 (65mJ),
Ion Energy Distribution of preIon Energy Distribution of pre--pulsed CO2 Laser Plasmapulsed CO2 Laser Plasma
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya25
TOF and Erosion Rate Measurement of CO2 Plasma
TOF results QCM (Au) erosion rate at same EUV output
0
0.02
0.04
0.06
0.08
0.1
0.12
1
Eros
ion
Rat
e (n
m/s
)
Nd:YAG CO2 laser(38mJ)
“Pre-pulse (Nd:YAG 5mJ) + CO2 (65mJ)”
@delay time 200ns
Nd:YAG 38mJ
Pre-pulse (Nd:YAG 5mJ) + CO2 (65mJ),
0
200
400
600
800
1000
1200
1400
1600
1800
0 200 400 600 800 1000Delay Time (ns)
Pea
k E
nerg
y (e
V)
0.0E+00
5.0E-09
1.0E-08
1.5E-08
2.0E-08
2.5E-08
3.0E-08
EU
V E
nerg
y (a
rb. u
nit)
Peak kinetic ion energy
ion kinetic energy drops with increasingdelay time
CO2 laser erosion rate is 64% of Nd:YAG erosion rate
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya26
Magnetic Field Ion mitigation for COMagnetic Field Ion mitigation for CO22 laser Plasma laser Plasma
Mirror
Laser
B
EUV
Xe Jet Nozzle
Ion
Magnetic Coil Magnetic Field
Laser QCM detector
Magnetic Coil Magnetic Field
Laser QCM detector
0
1000
2000
3000
4000
5000
6000
7000
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7
Magnetic Flux Density (T)
Ero
sion r
ate
YAG
CO2
Erosion rate was measured by QCM with same EUV output Nd:YAG and CO2 laser
CO2 : 0 T 0.6 T
Nd:YAG 32mJPre-pulse (Nd:YAG 5mJ) + CO2 (50mJ)
@delay time 200ns
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya27
Xe Droplet Target Generator
droplets generated in high vacuum (0.5Pa)
TMP
TMPSpectrometer
Droplets Nozzle with piezoelectric
Plasma
FlyingCircus II
Low vacuumbox
Xenon Droplets
High vacuum(0.5Pa)
YAG Laser
Controller Piezo Amp.
Delay Circuit
Laser Cont.
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya28
Xe droplet targetXe droplet target
5µs
Stationary
Irradiateddroplet
DropletsVelocity :20m/sFrequency:100kHzInterval :202µm
Irradiation Interval〈600µm 〉
15µs
required speedrequired speed
•• Droplet distance : > 600Droplet distance : > 600µµmm•• Driver laser frequency : 100kHzDriver laser frequency : 100kHz
••Required droplet speed : > 60m/sRequired droplet speed : > 60m/s
Xe droplet target for 100kHz operationXe droplet target for 100kHz operation
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya29
Laser irradiation
YAG
CO2
YAG-CO2
==Droplet==Velocity:20m/sDiameter:98µmSpacing:250µmFreqency:80kHz
==YAG==Energy : 5mJ
Pulse Duration : 8ns
==CO2==Energy : 50mJ
Pulse Duration : 25ns
EUV emission change with delay time between EUV emission change with delay time between prepre--pulse and main pulsepulse and main pulse
EUV emission with Xe dropletEUV emission with Xe droplet
Delaytime
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 0.2 0.4 0.6 0.8 1
Delay Time [us]
Max
EU
V Si
gnal
[a.u
.]
max. EUV emission at about 200ns
and preand pre--pulsed COpulsed CO2 2 Laser IrradiationLaser Irradiation
10µs afterYAG & CO2
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya30
HighHigh--power CO2 laser system for 10W at IFpower CO2 laser system for 10W at IF
Gas Cell
6.8kW
0.1 kW
Main-Amplifier< RF CO2 Laser >
Fast Axial Gas Flow RF-Excited Type
Pre-Amplifier< RF CO2 Laser >
Fast Axial Gas Flow RF-Excited Type
Oscillator< 100W/15ns
Pulse CO2 Laser >Wave Guide Type
~ 0.7 kW
Gas Circulating Pump
Isolator…saturable absorber is SF6 gas
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya31
Laser System Overview
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya32
Energy Levels of CO2 Laser (vibration)
CO2 N2
(100) (020)
(001)
(010)
V=1
10.6μm
9.6μm
Ener
gy L
evel
: 0.
291
eV
0.16
6 eV
Quantum efficiency: (0.291eV-0.166eV)/0.291eVx100=43%
( He for fast relaxation )
Relaxation time: ~100µs
Relaxation time: ~1µs
Relaxation time: ~10µs
0.4~60µs
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya33
Extraction Efficiency
Es : saturation fluenceEmax :maximum outputEin : input fluenceEout : output fluence
τp : pulse widthτr : rotational relaxational time
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya34
P(20) oscillator output power vs. rep. rate
020406080
100120140160180
0 20 40 60 80 100PRF, kHz
Ave
rage
Pow
er, W
0.00.51.01.52.02.53.03.54.04.55.0
Pow
er G
ain
Oscillator Power
Amplfier Power
2nd Amplifier Power
Power Gain
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya35
Amplifier / RF pumped axial flow CO2 Laser
TLF5000 (5W) &TLF15000 (15kW)
Laser InputLaser Output
Optical path
Laser equipment
Laser Head
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya36
2 stage experiment : two cw 5kW lasers
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya37
CW amplification of TLF5000
Gain Length L= 240 cmDiameter D= 1.4 cm
Small Signal Gain g0=0.99 [%/cm]Saturation Intensity Is=1624 [W/cm2]
0 200 400 600 800 10000
500100015002000250030003500 Least Square Fitting
Out
put P
ower
[W]
Input Power [W]
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya38
Experimental Arrangement (15ns Pulse Amplification)
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya39
Pedestal Control
-1 0 1 2 3 4
-10
0
10
20
30
40
50
Peak
Pow
er
(kW
)
Time(µs)
0torr 3torr
SF6 Saturable Absorber
CdTe Pockels Cell
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya40
Amplification of 15ns pulse by TLF5000
Input energy: 1.6μJOutput energy: 6.1μJ
0
0.2
0.4
0.6
0.8
1
1.2
0.00 0.05 0.10 0.15Time [µs]
Inte
nsity
[Arb
. Uni
ts]
Inout
0.0
0.5
1.0
1.5
2.0
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3.0
3.5
4.0
0.00 0.05 0.10 0.15 0.20
Time [µs]
Inte
nsity
[Arb
. Uni
ts]
Inout
FWHM: 15ns
Small signal amplification
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya
Beam Profile without and with RF pumping
Amplifier Exit(without pumping)
Amplifier Exit(withCW pumping)
No beam quality degradation observed
US-Japan workshop on Heavy Ion Fusion Sept28-30, 2005, Utsunomiya42
SummarySummaryEUV light source by COEUV light source by CO22 laser driven Xe droplets for laser driven Xe droplets for HVM was characterized.HVM was characterized.
For 115W light source alternative technologies (RF-CO2, droplet, magnetic field mitigation) are considered.
Testing feasibility with TEA CO2 laser systemPre-pulse laser increases conversion efficiency.Xenon droplet target has been generated in high vacuum.Effectiveness of magnetic field ion mitigation has been experimentally
confirmed.
Achieved performance:Achieved performance:LPP Source by YAG laser LPP Source by YAG laser
-- InIn--band Powerband Power 5.7 W (2%BW) at IF <Estimate> 5.7 W (2%BW) at IF <Estimate> -- Conversion EfficiencyConversion Efficiency 0.9 % @ 10kHz (2%BW, 2p sr)0.9 % @ 10kHz (2%BW, 2p sr)by CO2 laserby CO2 laser-- Conversion EfficiencyConversion Efficiency 0.6 % @ 10Hz (2%BW, 2p sr)0.6 % @ 10Hz (2%BW, 2p sr)
max. EUV emission at delay time of 200ns-- Short Pulse 6kW CO2 laser is under developmentShort Pulse 6kW CO2 laser is under development