Effect of the Deposition Condition on Properties of a-Si: F: H Films

We prepared a-Si: F: H films from SiF 4 and H 2 mixture gas by three discharging methods (DC, CSDC, and RF). The fluorine concentrations for the DC, CSDC and RF films are 15 at.% 1.5 at.% and 0.5 at.%, respectively. Optical emission spectra from the discharging gas suggest that the kinetics of the chemical reaction on the substrate surface is essential for the film formation and the cathode screen considerably affects the plasma condition. Even 1.5 at.% incorporated fluorine atoms have the effect to reduce the optically induced conductivity change. When the nondoped a-Si: F: H layer is deposited onto the doped film, considerable amount of doped atoms are incorporated in to the nondoped layer.