Film-growth precursor in hydrogenated microcrystalline silicon grown by plasma-enhanced chemical vapor deposition

Film-growth precursor for microcrystalline silicon (μc-Si:H) thin films was studied by growing the films in the presence of an electric field by using plasma-enhanced chemical vapor deposition. μc-Si:H films were prepared using either hydrogen- or argon-diluted silane, which usually result in μc-Si:H films with a crystalline volume fraction of more than 75%. It was observed that for both the films the crystalline phase is markedly suppressed in the presence of an electric field. In particular, this suppression is greater for the films grown near the anode side. For the films grown near the anode side, little or no crystalline phase was observed. A possible precursor responsible for the formation of μc-Si:H will be discussed.