Laser produced plasma light source for HVM-EUVL

A major technical challenge of an extreme ultraviolet (EUV) light source for microlithography at 13.5 nm is the in-band power requirement of more than 115 W at the intermediate focus. The solution for HVM EUV lithography is a laser produced plasma light source with a cost effective CO
₂
drive laser and a high conversion efficiency Sn target. To demonstrate this, a LPP source is developed for high volume manufacturing EUV lithography which is based on a high power CO
₂
MOPA (Master Oscillator Power Amplifier) system and a tin target. It is concluded that the CO
₂
laser driven Sn light source is the most promising candidate for HVM EUVL due to its scalability, high efficiency and long collector mirror lifetime.