Growth mechanism of microcrystalline silicon obtained from reactive plasmas

Three models proposed for the growth mechanism of hydrogenated microcrystalline silicon films (μc-Si:H) from reactive (silane and hydrogen mixture) plasmas are reviewed. The `etching model' is discussed using experimentally obtained relationship between radical generation rate in plasmas and growth rate of films. The `chemical annealing model' is investigated through the growth of films using a layer-by-layer method with and without cathode shutter. Substrate-temperature dependence of crystallinity of the resulting films and initial growth behavior of silicon films on atomically flat GaAs substrate clearly support the ‘surface diffusion model’.