DIRECT DIAGNOSTIC TECHNIQUE OF HIGH-INTENSITY LASER PROFILE BASED ON LASER-COMPTON SCATTERING

摘要

A high-intensity laser is essential for plasma generation for EUV (Extreme Ultraviolet) lithography, which is studied as the next generation of ultra-fine semiconductor lithography. Nevertheless, there is no way to directly measure profile of high-intensity laser at the present day. Therefore, we have been developing a method for measuring high-intensity laser profile based on the laser-Compton scattering using Cs-Te photo cathode RF-Gun at Waseda University. Specifically, laser profile is obtained by scanning the electron beam which is focused to about 10 μm by solenoid lens. We have simulated beam size focused by solenoid lens using tracking code GPT (General Particle Tracer) and optimized the beam parameter to obtain beam size of 10 μm. Then, we have installed solenoid lens and generated focused beam. We measured beam size using radiochromic film called GAFCHROMIC dosimetry film type HD-810. In this conference, we will report the result of GPT simulations, beam size measurements, the present progress and future prospects.