Microcrystalline-silicon thin films prepared by chemical transport deposition

We have investigated on the production of microcrystalline-silicon (μc-Si) films from solid Si sources by the chemical transport deposition, and could obtain photo-sensitive μc-Si films. The crystallinity and photo-sensitivity of μc-Si films are improved by increasing hydrogen pressure and the highest photo-sensitivity of 50 times is obtained at 200 Pa. The high density of atomic hydrogen probably causes the defect passivation in the high-pressure conditions. The distance between the Si target and the substrate is also important to improve the film properties, and a shorter distance is effective for higher deposition rate, crystallinity and photo-sensitivity.