Processing of amorphous Si by pulsed laser irradiation at different wavelengths

Amorphous Si thin films deposited on thermally oxidized Si wafers have been processed by the 2nd and 3rd harmonics of Nd:YAG laser. Surface modification of amorphous silicon layers have been investigated by scanning electron microscopy before and after chemical etching of processed silicon films. The super-lateral crystal growth regime was achieved with laser fluence of 280 mJ/cm2 for the 2nd harmonics and 155 mJ/cm2 for the 3rd harmonics. The grain size in polycrystalline Si samples prepared by successive crystallization in the lateral growth regime is about 0.5 - 1 μm.