Electron drift mobility measurements on annealed and light-soaked hydrogenated amorphous silicon

Abstract

We measured the effects of light soaking on the electron drift mobility for three specimens of hydrogenated amorphous silicon (a-Si:H) from different laboratories. The temperature range 130–300 K was studied. The measurements in all cases reveal two temporal regimes: an early time regime associated with bandtail transport, and a later-time regime associated with deep trapping of the electrons. We found no evidence for effects of light soaking on the bandtail regime within a reproducibility error of 20%. Deep trapping was significantly affected by light soaking, in agreement with extensive prior measurements.