Temperature Dependence of the Photoconductivity and the Near Absence of Light-Induced Defects in a-SixGe1-x:H

Abstract

AbstractThe photoconductivities ap of glow discharge deposited a-Ge:H and amorphous Si-Ge alloys prepared in different laboratories were measured between 4.2K and 300K and compared with σp(T) of intrinsic and compensated a-Si:H films. The alloys as well as a-Ge:H do not exhibit thermal quenching of σp(T) at elevated temperatures which suggests that the valence and conduction band tails have similar widths. Remarkable is the near absence of light-induced metastable defects in the alloys as well as in a-Ge:H even after prolonged exposures at low temperatures.