Polycrystalline Silicon Films on SiO2 Substrate Treated by Excimer Laser Annealing

Selected area laser-annealed polycrystalline silicon (p-Si) thin films were prepared by a 248 nm excimer laser. 1 gm thick p-Si films with grain size less than 100 nm were deposited on SiO2 substrate by chemical vapor deposition using atmospheric pressure (APCVD). Grain sizes before and after annealing was examined by scanning electron microscopy (SEM) and the mechanism of grain growth was discussed in detail. The maximum grain size of a selected area laser-annealed p-Si film can be increased from 100 nm up to 2.9 mu m on SiO2 substrate by using appropriate laser energy densities. It indicated that silicon grains in laser-annealed regions had grown up competitively with three stages.