High-quality a-SiGe:H produced by nanometer deposition and hydrogen plasma annealing

Abstract

High-quality narrow bandgap (<1.5 eV) a-SiGe:H films have been fabricated by alternately repeating the deposition of a few nanometer thick a-SiGe:H layer and hydrogen plasma annealing. With increasing hydrogen plasma annealing time, both the hydrogen content and optical bandgap are decreased and photosensitivity has been improved to >10/sup -5/ S/cm and >10/sup 4/, respectively. It is shown that the metastable states are also reduced by hydrogen plasma annealing.