基于Xe的惰性和在13~14nm波段高的辐射强度,Xe被认为是极紫外投影光刻(EuVL)潜在的靶材,为此设计和研制了一台液体微滴喷射靶激光等离子体(LPP)极紫外光源。详细地研究了Xe液体微滴喷射靶的光谱辐射特性、在13.4nm的激光-EUV转换效率、辐射稳定性及碎屑产生状况。实验结果表明,Xe在13.4nm的最高转换效率可以达到0.75%/2πsr/2%bw,辐射稳定性±4%(1σ),在激光打靶10^5次后无碎屑产生。
Xenon is a promising target material in Extreme Ultraviolet Lithography(EUVL) for its high EUV intensity in 13-14 nm and no condensation on multilayer mirror surfaces due to chemical inert,and therefore a Laser Produced Plasms (LPP) source with liquid aerosol spray target is designed and developed in this paper. The spectral radiation characteristics,laser-to-EUV conversion efficiency at 13.4 nm and debris production by target material erosion or deposition of the liquid Xe aerosol spray target are studied in detail. Experimental results show that the maximum conversion efficiencey of Xe is 0. 75%/2π sr/2%bw at 13.4 nm,and pulse-pulse sability is ±4%(1σ) at 0. 5 mm laser-nozzle diatance,the results also show that liquid Xe aerosol spray target LPP source can almost eliminate debris after 10^5 laser shots.