Sources for EUV lithography

The two main sources used in commercial EUV lithographic exposure tools comprise laser-produced plasma sources and discharge-produced plasma sources.  

Hudyma, An overview of optical systems for 30 nm resolution lithography, Proc. SPIE 4832, 137 148 (2002) R.M. Hudyma, H. J. Mann, U. Dinger, and P. Kurz, Projection system for EUV hthography, U.S. Patent No. 6,985,210 (2006). 

Kleinschmidt, K. Gabel, et al., EUV source power and lifetime the most critical issues for EUV hthography, Proc. SPIE 5374, 133 144 (2004) M. Richardson, C. S. Koay, K. Takenoshita, et al., Laser plasma EUVL sources progress and challenges, Proc. SPIE 5374, 447 453(2004). 

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