Development of the 1st generation laser-produced plasma source for EUV lithography

We report on latest status of the 1st generation laser-produced plasma source system ("ETS" device) for EUV lithography. The device consists of the original concepts: (1) CO2 laser driven plasma, (2) hybrid CO2 laser system that is combination of high speed (>100 kHz) short pulse oscillator and industrial cw-CO2 laser, (3) magnetic mitigation, and (4) double pulse EUV plasma creation. Maximum burst on time power is 104 W (100 kHz, 1.0 mJ EUV power @ intermediate focus), laser-EUV conversion efficiency is 2.5 %, duty cycle is 20 % at maximum. Continuous operation time is so far up to an hour.