INFLUENCE OF CHAMBER PRESSURE ON HYDROGEN-BONDING CONFIGURATIONS IN A-SIGE-H FILMS PREPARED BY PHOTO-CVD

Hydrogenated amorphous silicon-germanium (a-SiGe:H) thin films have been deposited by the process of mercury sensitized photo-CVD method from a mixture of silane and germane gases. The growth processes of a-Si:H and a-Ge:H films have been studied at different chamber pressures and from these data optimum pressures for the deposition of a-SiGe:H films have been selected. The variations of the electrical and structural properties of these films with optical band gap have been studied with films deposited at different chamber pressures. The properties of a-SiGe:H films have been found to be better at lower chamber pressure and the data is interpretated on the basis of changes in hydrogen bonding configuration with pressure.