EUV Source Supplier Update, Gigaphoton Hakaru Mizoguchi EUV Source Workshop 6 May, 2007 Baltimore, MD, USA Acknowledgments A part of this work was performed under the management of EUVA in the NEDO's R&D Program.
Outline Introduction - LPP source roadmap and concept Update of CO 2 laser produced Sn plasma source - Laser output power - Sn deposition analysis - System scalability LPP/EUV future direction to HVM Summary P2
LPP Source Roadmap 1st Mid term 2004/9 2 nd Mid term 2006/3 EUVA Final 2008/3 HVM source-1 2010 planning EUV Power (IF) Stability Laser Laser freq. CE (source) Target 5.7W 1) --- YAG:1.5kW 10kHz 0.9% Xe-Jet 10W 1) s<±10% CO 2 :2.6kW 100kHz 0.9% SnO 2 choroid liquid jet EUVA project 50W 2) s <±5% CO 2 : 7.5kW 100kHz 2.5% Sn-Droplet 110W 2) /140W 3) 3s<±0.3% CO 2 : 10kW 100kHz 4% Sn-Droplet Gigaphoton Technology for <10W Nd:YAG Laser, Liquid Xe jet Technology for 115-200W CO2 Laser, Sn droplet target Magnetic field mitigation Note) Primary source to IF EUV transfer efficiency: 1) 43% 2) 28% with SPF 3) 36% without SPF P3
Light Source Concept Requirement for EUV source for HVM High EUV power >115 W EUV Stability Collector mirror lifetime Low CoG / CoO Original Concepts CO 2 laser + Sn LPP light source + Magnetic field mitigation Sn target supply High power pulsed CO2 laser system Pulsed CO 2 Laser OSC+cw-CO2 laser AMP IF Magnetic field mitigation P4
History of technical concept proposal & technical demonstration 2001: Original Concept of CO 2 laser based LPP source. (Patent applied in 2001) Original Concept of MOPA CO 2 laser based LPP source. (Patent applied in 2001) 2002 /09: EUVA light source project start with Gigaphoton, USHIO and Komatsu 2003: Original Concept of Magnetic field ion mitigation (Patent applied in 2004) 2004 /09: EUV 5.7 W IF was demonstrated (Nd:YAG and Xe jet) 2006 /03: EUV 10 W IF was demonstrated (CO 2 and SnO 2 choroid liquid jet) 2007 /02: EUV 40 W IF was demonstrated (CO 2 and Sn target) 2007 /04: EUV 47 W IF was demonstrated (CO 2 and Sn target) This report P5
Outline Introduction - LPP source roadmap and concept Update of CO 2 laser produced Sn plasma source - Laser output power - Sn deposition analysis - System scalability LPP/EUV future direction to HVM Summary P6
Update of CO 2 laser produced Sn plasma source Original concept: CO 2 laser + Sn LPP light source for HVM EUVL Update from Feb. 2007 (Advanced Microlithography @ San Jose) Laser output power CO 2 laser power 6.0 kw 7 kw Topic 1 System scalability 20-kW single line CO 2 system is scalable Topic 2 Sn deposition analysis Low density Sn deposition Topic 3 P7
Experimental devices for EUV source development at EUVA Component development is driven by two experimental devices. 1. High power experiment device RF-CO 2 laser based system High power laser system development Target development High power EUV generation Target Chamber 2. Fundamental experiment device TEA-CO 2 laser based system CE experiment Debris analysis Mitigation system development P8
Topic 1 High Power CO 2 Laser MOPA System Performances Laser Power: 6kW 7 kw Pulse Width: 22 ns Repetition Rate: 100 khz Laser System Main-Amplifier [Fast Axial Gas Flow RF-Excited CO 2 laser(cw 15kW)] Oscillator [Wave Guide Q-switched CO 2 laser] Repetition rate:100khz Pulse width: 22ns High power experiment device 7kW Pre-Amplifier [Fast Axial Gas Flow RF-Excited CO 2 laser(cw 5kW)] Oscillator P9
Topic 1 CO 2 Laser MOPA System Average Output Power Amplification Characteristic of Main - Amp High power experiment device 10000 Now 8000 Output Power [W] 6000 4000 2000 0 Rep. rate: 100 khz Duty: on 10ms, off 90ms Operation : Continuous (no time limit) 0 500 1000 1500 2000 2500 3000 Input Power [W] ( to Main-AMP ) P10
Topic 1 EUV from high power CO 2 laser produced Sn plasma High power experiment device EUV source power : 110 W (130 W) (2 πsr, 2%bw) Target : Rotating Sn plate Laser irradiation power: 5 kw ( 6 kw) Conversion efficiency (CE): 2.2 % EUV energy stability : 8% (3σ, 50 pulse) 1.6 1.4 EUV energy [mj] 1.2 1 0.8 0.6 0.4 0.2 0 0 100 200 300 400 500 600 700 800 Number of pulses P11
Topic 1 LPP/ EUV Output Power High power experiment device LPP IF EUV power caught up the 1 st gen. Sn base-dpp power level! IF EUV power (W) 100 80 60 40 20 DPP LPP Now 2 nd gen. Sn base DPP 1 st gen. Sn base DPP 0 2002 2003 2004 2005 Year 2006 2007 2008 Transmittance from primary to I/F DPP LPP Primary source EUV power (2pi sr, 2%bw) 616-702 W 110 W (130 W) Debris shield transmission 0.8 1.0 Collection angle & collector transmission 0.28 0.38 (4 sr, R=0.6) Aperture (etendue limit & SPF) transmission 0.45 0.09 1.0 0.36 Gas transmission 0.9 0.94 Usable EUV power after IF 55-62 W 40 W (47 W) w/o SPF DPP data based on EUVA / DPP, October 2006 P12
Topic 2 Multi 10 kw Short Pulse CO 2 laser MOPA system AMP1 RF-excited CO2 laser Pumping : 50 kw 20 kw (200mJ at 100kHz) Multi-line Oscillator Rep. rate :100kHz pulse width :20 ns (FWHM) AMP2 RF-excited CO2 laser Pumping power : 120 kw AMP3 RF-excited CO2 laser Pumping power : 120 kw One beam, 20 kw is reasonable estimate!! Details will be discussed at. Power Limitation Damage of Optics Short pulse damage threshold lower than CW threshold Filling Factor Laser beam diffraction Saturation Re-absorption from lower laser level (?) P13
Sn debris and mitigation Debris from Sn laser plasma and mitigation Fundamental experiment device Droplet debris Sn neutral Fast ion Deposition Sputtering Minimized by CO 2 irradiation Magnetic field mitigation Experimental layout 90deg 75deg 75deg 60deg QCM array lens Plasma 45deg 45deg FC2 (EUV energy) QCM 22.5deg (Deposition/sputter) 22.5deg Faraday Cup (Ion) Si witness plate (debris) Faraday-cup array TEA-CO 2 laser P14
Topic 3 CO 2 laser is clean LPP driver compared to YAG Fundamental experiment device Sputter / deposition rate measured by QCM 9.0E-03 sputter & deposition rate [nm/mj] 8.0E-03 7.0E-03 6.0E-03 5.0E-03 4.0E-03 3.0E-03 2.0E-03 1.0E-03 0.0E+00-1.0E-03 Deposition Nd:YAG CO2 Deposition case Deposition Sputtering 0 15 30 45 60 75 90 Observation angle [deg] No deposition Mo/Si sample test P15
Topic 3 Experimental setup Mo/Si sample mirror test Mo/Si mirror sample :10 bilayer Distance from plasma: 120mm Angle to laser incidence: 30 degree Laser pulse energy: 15-25mJ Laser pulse number: 1.5 10 5 pulse Chamber pressure: 5 10-2 Pa Fundamental experiment device TEM class sectional image of the exposed Mo/Si 4-nm uniform Sn deposition Mo/Si mirror Sn plate TEA-CO 2 Laser Low density Sn deposition; since the measured reflectivity change is much smaller than the calculated reflectance for 4nm solid Sn. P16
CO 2 laser is clean LPP driver compared to YAG Electron density n c Hot dense plasma X-ray emission Laser Laser plasma interaction region Efficient EUV is emitted from hot dense plasma near the electron critical density nc. n n c ε0mω = 2 e 2 1.11 10 2 λ Fundamental experiment device 21 3 c = (cm ) λ: wavelength in μm 0 Distance Cut off density :Nc 1 1/100 Laser Electron critical density (cm -3 ) CO 2 (10.6um) 1.0x10 19 CO 2 Yag ω Nd:YAG (1.06um) 1.0x10 21 CO 2 laser light is efficiently absorbed by low density plasma, therefore thermal boiling of Sn (cause of Sn drops creation) is avoided. P17
Outline Introduction - LPP source roadmap and concept Update of CO2 laser produced Sn plasma source - Laser output power - Sn deposition analysis - System scalability LPP/EUV future direction to HVM Summary P18
LPP/EUV future direction to HVM (1) LPP Power Roadmap EUV power estimation with laser power & CE CE % Laser kw 2.0 2.2 2.5 3.0 3.5 4.0 4.5 2.5 14 15 18 21 25 28 32 18 20 23 27 32 36 41 5.0 28 31 35 42 49 56 63 36 40 45 54 63 72 81 7.5 42 46 53 63 74 84 95 54 59 68 81 95 108 122 10.0 56 62 70 84 98 112 126 72 79 90 108 126 144 162 HVM source Transfer efficiency from primary source to IF HVM-source Total Debris Collectable Reflectivity shield angle T% SPF Case1 0.28 0.8 5sr 0.6 0.9 0.8 Case2 0.36 1 4sr 0.6 0.94 1 P19
LPP/EUV future direction to HVM (2) Collector mirror lifetime estimation based on this work 1000 701 Bpls (10.5months) mirror lifetime [Bpls] 100 350 Bpls (5.2months) 175 Bpls (2.6months) HVM-source 87 Bpls (1.3months) 10 0 50 100 150 200 250 IF power [W] Lifetime requirements (12months) : 80Bpls@10kHz 800Bpls@100kHz Mirror lifetime estimation based on Rep.rate : 100kHz, CO 2 laser w/o pre-pulse Mirror : Mo/Si 250 bilayer, 22.5deg(worst place) Plasma-mirror distance : 150mm Magnetic field effect : 1000 Tool duty: 25% 7days 24H operation P20
LPP technology update summary LPP power by EUVA set up (non-integrated setup) 40W@I/F is achieved at Q4 2006. Now 47W@I/F equivalent! By CO2 laser (6kW 7kW) produced Sn plasma Target: solid Sn disk Source power 110 W 130W, 2p sr, 2%bw 20KW driver laser scalability is estimated. Easier debris mitigation of CO2 laser produced Sn plasma 175 Bpls factor 1000 (detection limit) Estimated number by experimental setup. Need proven data with system demonstration. Very small damage on collector mirror is observed For next stage SD (System Demonstration)-SoCoMo is under planning 90W (@ I/F) with CO2 laser and Sn droplet + debris mitigation+ Collector mirror P21