Bonding Defects in Hydrogenated Amorphous Silicon

A mechanism for charged-carrier-trapping-inducedde fect metastability in hydrogenated amorphous silicon (a-Si:H) and in hydrogenated amorphous silicon alloys containing relatively high concentrations of oxygen and/or nitrogen atoms (a-Si:X:H, X = O or N) is described. The experimental results that identified this defect metastability mechanism were i) differences in the Staebler-Wronski effect in a-Si:H and a-Si:N:H alloys prepared from N2 and NH3 source gases by remote plasma-enhanced chemical-vapor deposition, and ii) differences in defect generation at N-atom terminated Si-SiO2 interfaces prepared from NH3 and N2O.