Photo-induced reversible change of Urbach edge in hydrogenated amorphous silicon

Abstract

Photoconductivity spectra temperature dependence combining with transmission measurements have been formed on hydrogenated amorphous silicon. After exposure by AM1 light a reversible increase of 6% of the Urbach parameter E0(T,X) has been observed. This is a direct evidence for the fact that photo-induced changes in a-Si:H create not only metastable defects but also affect the topological disorder.