DEPOSITION MECHANISM OF HYDROGENATED AMORPHOUS SI-GE FILMS

The deposition rates for hydrogenated amorphous silicon, hydrogenated amorphous germanium and hydrogenated amorphous Si-Ge alloys, prepared by the plasma chemical vapour deposition method, are presented as functions of the substrate temperature. On the basis of the experimental results the behaviour of hydrogen on the growing surface is discussed quantitatively using a simplified model. The selection of long-lifetime radicals (such as SiH3 and GeH3) and the hydrogen-coverage factor are stressed as two key factors for controlling not only the deposition process but also the structural and electronic properties of the resultant alloy films.