Crystallization of Silicon Thin Films by Infrared Semiconductor Laser Irradiation Using Carbon Particles

*** We report the crystallization of 40-nm-thick hydrogenated amorphous silicon films using 940nm continuous wave infrared semiconductor laser with 200 nm diameter carbon particles as photo absorption. The laser beam was focused to 100 μm diameter at the surface of carbon particles. Laser irradiation at 25 W heated the carbon surface region to about 3430 K, which was estimated by analysis of spectra of light emission caused by laser irradiation when quartz substrates were placed on the surface of carbon particles. The silicon films coated with SiO2 films were crystallized by laser irradiation for 170 μs at 25 W. The crystallization volume ratio was 0.53. Crystallization over 1.1 mm area was also demonstrated by laser irradiation at 25 W.