Visible photoluminescence in hydrogenated amorphous silicon grown in microwave plasma from SiH4 strongly diluted with He

The room temperature visible photoluminescence of wide-band gap hydrogenated amorphous thin films is described. The films were prepared in silane microwave plasma strongly diluted with He under electron resonance conditions by the MW ECR PE CVD method. The films were characterized by optical and infrared absorption, hydrogen thermal desorption, and Raman scattering. The results showed two types of photoluminescence: one related with oligosilanes and the other with electron-hole recombination in tail states.