Melting and solidification of microcrystalline Si films induced by semiconductor diode laser irradiation

Rapid thermal annealing of microcrystalline, Si (mu c-Si) films induced by cw semiconductor diode laser (SDL) irradiation has been investigated. Owing to the higher absorption coefficient of mu c-Si than that of amorphous Si (a-Si), 1.2-mu m-thick mu c-Si films are melted and recrystallized within 3 ms, whereas no phase transformation of a-Si films is observed under the same annealing condition. The annealed Si films show a high crystalline volume fraction of 97% and [111] preferential orientation. Characteristic triangle surface structures aligned to the laser scanning direction, which suggests that the lateral solidification from molten Si is observed.