Role of hydrogen dilution in improvement of a-SiGe:H alloys

Abstract

The reasons for the improvement of the properties of a-SiGe:H when using hydrogen diluted gas mixtures are reappraised and it is suggested that reduction of the contribution of short-lifetime-radicals to film-growth is the responsible cause. Using disilane-germane gas mixtures, very low power density and reasonably high pressure, the preferential depletion of germane to prepare material which is comparable to that prepared using hydrogen-diluted silane-germane gas mixtures has been avoided.