Laser Produced Plasma Light Source for HVM-EUVL

Transcription

1 Laser Produced Plasma Light Source for HVM-EUVL Akira Endo, Hideo Hoshino, Takashi Suganuma, Krzysztof Nowak, Tatsuya Yanagida, Takayuki Yabu, Takeshi Asayama, Yoshifumi Ueno, Masato Moriya, Masaki Nakano, Hiroshi Someya, Toshihiro Nishisaka, Tamotsu Abe, Georg Soumagne, Hiroshi Komori, Hakaru Mizoguchi, Akira Sumitani and Koichi Toyoda EUVA (Extreme Ultraviolet Lithography System Development Association, Japan) International EUVL Symposium 30 October, 2007 Sapporo, Japan Acknowledgments This work was supported by the New Energy and Industrial Technology Development Organization -NEDO- Japan. 1 International EUVL Symposium 2007

2 Outline Introduction - LPP source roadmap and concept - Update of CO 2 laser produced Sn plasma source CO 2 laser produced Sn plasma source - High power CO2 laser system - EUV output evaluation at intermediate focus - Sn droplet target control - Sn deposition analysis and mitigation LPP/EUV future direction to HVM - System scalability Summary 2 International EUVL Symposium 2007

3 LPP Source Roadmap 1st Mid term 2004/9 2 nd Mid term 2006/3 EUVA Final 2008/3 HVM source planning EUV Power (IF) Stability Laser Laser freq. CE (source) Target 5.7W 1) --- YAG:1.5kW 10kHz 0.9% Xe-Jet 10W 1) σ<±10% CO 2 :2.6kW 100kHz 0.9% SnO 2 choroid liquid jet EUVA project 50W 2) σ <±5% CO 2 : 7.5kW 100kHz 2.5% Sn-Droplet 110W 2) /140W 3) 3σ<±0.3% CO 2 : 10kW 100kHz 4% Sn-Droplet Gigaphoton Technology for <10W Nd:YAG Laser, Liquid Xe jet Technology for W 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 3 International EUVL Symposium 2007

4 Light Source Concept Requirement for EUV source for HVM High EUV power >115 W EUV Stability Collector mirror lifetime Low CoG / CoO CO 2 laser + Sn LPP light source + Magnetic field mitigation Sn target supply High power pulsed CO 2 Laser IF Magnetic field mitigation 4 International EUVL Symposium 2007

5 Experimental devices for EUV source development Component development is driven by two experimental devices. 1. High power experiment device RF-CO 2 laser based system High power laser system development High power EUV generation Intermediate focus evaluation Target Chamber 2. Fundamental experiment device TEA-CO 2 laser based system CE experiment Debris analysis Mitigation system development Target development 5 International EUVL Symposium 2007

6 Update of CO 2 laser produced Sn plasma source Original concept: CO 2 laser + Sn LPP light source for HVM EUVL Update from May 2007 (EUV source workshop, Baltimore) Laser output power CO 2 laser power 7 kw 8 kw, continuous Topic 1 IF (intermediate focus) evaluation IF EUV power 60 W Topic 2 Sn droplet target Sn droplet active control Topic 3 Sn deposition analysis Uniform Sn deposition Topic 4 6 International EUVL Symposium 2007

7 Outline Introduction - LPP source roadmap and concept - Update of CO 2 laser produced Sn plasma source CO 2 laser produced Sn plasma source - High power CO 2 laser system - EUV output evaluation at intermediate focus - Sn droplet target control - Sn deposition analysis and mitigation LPP/EUV future direction to HVM - System scalability Summary 7 International EUVL Symposium 2007

8 High power CO 2 laser MOPA system Performances Laser Power: 8 kw Pulse Width: 20 ns Repetition Rate: 100 khz Beam quality : M2 1.1 Topic 1 High power experiment device See poster SO-P29 Laser System 60W 3 kw 8 kw Oscillator Wave length: 10.6um Rep. rate :100kHz Pulse width :20 ns (FWHM) Pre-Amplifier RF-excited CO2 laser Main-Amplifier RF-excited CO2 laser Oscillator Target Chamber 8 International EUVL Symposium 2007

9 High power CO 2 laser MOPA system Topic 1 High power experiment device Output laser beam characteristics Temporal pulse shape Beam quality Laser beam profile Intensity Time 50 ns/div. Beam Diamater (μm) After amplification Ocillator 3000 f= 508mm Distance form focusing lens (mm) Pulse duration : 20 ns (FWHM) Pedestal component : <10% Beam quality: M2=1.1 No significant change after amplification. 9 International EUVL Symposium 2007

10 High power CO 2 laser MOPA system Topic 1 High power experiment device Output laser beam characteristics Pulse energy stability : 2% (3σ, 500 pulses) 2.5 Laser pulse energy (arb. unit) Number of pulses 10 International EUVL Symposium 2007

11 EUV output evaluation at intermediate focus Topic 2 High power experiment device System configuration EUV chamber Oscillator Collector mirror 1sr (=3sr x 1/3) IF (intermediate focus) Oscillator Pre-Amp Main Amp Rotating Sn plate target 11 International EUVL Symposium 2007

12 EUV output evaluation at intermediate focus EUV IF power : 16 W (measured by 1sr collector) 60 W (4 sr collector, calculated) Target : Rotating Sn plate Laser irradiation power: 6 kw (100 khz, 20 ns) EUV energy stability : 3.8% (3σ, 500 pulses) IF image size : 3.6 mm (H), 3.3 mm (V) at 1/e^2 Etendue : 1.9 mm 2 sr (4 sr collector) Topic 2 High power experiment device EUV energy@if [mj] EUV pulse energy at intermediate focus point Number of pulses 12 International EUVL Symposium 2007

13 EUV output evaluation at intermediate focus Topic 2 High power experiment device IF image (EUV in-band) Y Z X IF size FWHM (mm) 1/e 2 (mm) X Y X Y Beam Profile on x-axis Beam Profile on y-axis Intensity (arb. unit X-axis Intensity (arb. unit Y-axis Position (mm) Position (mm) 13 International EUVL Symposium 2007

14 Sn droplet target control See poster SO-P31 Topic 3 Sn droplet charging Sn droplet generation Droplet generator Piezo. Piezo. Driver Syncro. Charging Electrode Charging controller Deflection Electrode Freq : 142kHz 500kHz Size : d=40 um 20 um δ Back light CCD 14 International EUVL Symposium 2007

15 Sn droplet target control Topic 3 Deflecting electrode 1mm Material: Sn Droplet : d =40 um Deflection : 1/10 : 4 mm 4mm 15 International EUVL Symposium 2007

16 Sn deposition analysis -Target dependency- Topic 4 Fundamental experiment device Sn deposition without magnetic field Experimental setup CO2 laser, 100kHz Mo/Si sample TEM cross sectional image of the samples 60deg 100mm Sn plate target Sn grain d=100 nm Sn wire target (mass limited) Uniform Sn layer 50nm 50nm 16 International EUVL Symposium 2007

17 Ion suppression by magnetic field intensity [a.u.] Faraday cup signal with and without magnetic field T 1T Topic 4 Fundamental experiment device Experimental setup time [us] Integrated ion signal versus magnetic flux density. 1 Ion signal [a.u.] noise level B-field [T] See poster SO-P31 17 International EUVL Symposium 2007

18 Mo/Si sample mirror test with B field Topic 4 Fundamental experiment device Experimental conditions Mo/Si mirror sample :10 bilayer Distance from plasma: 60 mm Angle to laser incidence: 45 degree Laser pulse energy: 20 mj Laser pulse number: pulse Static experiment (zero Sn vapor recovery) TEM cross sectional image of the exposed Mo/Si Before exposure B= 0 T 4.5 nm uniform Sn 1 nm uniform Sn B= 1 T 10nm 18 International EUVL Symposium 2007

19 Sn ion from CO 2 plasma Topic 4 Fundamental experiment device Sputter yield of Si by Sn ion 10 Deposition under 2keV sputter yield [atom/ion] Sn ion energy [kev] 2keV Si Sn ion TOF signal ion signal [V] sputter deposition 15deg 30deg 60deg 75deg time[us] 19 International EUVL Symposium 2007

20 Outline Introduction - LPP source roadmap and concept - Update of CO 2 laser produced Sn plasma source CO 2 laser produced Sn plasma source - High power CO 2 laser system - EUV output evaluation at intermediate focus - Sn droplet target control - Sn deposition analysis and mitigation LPP/EUV future direction to HVM - System scalability Summary 20 International EUVL Symposium 2007

21 20 kw short pulse CO 2 laser 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 A 20 kw, single-beam CO2 laser is feasible which corresponds to 280 W in-band EUV at IF (CE=4%). Power Limitation Damage of Optics Short pulse damage threshold lower than CW threshold Filling Factor Laser beam diffraction Saturation Efficient amplification method 21 International EUVL Symposium 2007

22 Summary LPP source at EUVA (non-integrated setup) EUV output evaluation at intermediate focus. 60 W at I/F achieved. Preliminary target: solid Sn disk. 8 kw drive laser output power; scalable to 20 kw. Sn droplet active control. (poster presentation SO-P31) Magnetic debris mitigation of CO 2 laser produced Sn plasma. Sn deposition reduced by magnetic field. Neutral Sn deposition and countermeasures will be studied. Integrated system demonstration (SD) planned. Next step (integrated setup) Integrated system demonstration and mirror lifetime evaluation. 22 International EUVL Symposium 2007