Subgap excitation of defect band photoluminescence in phosphorous doped hydrogenated amorphous silicon

Abstract

This article presents a study of the effect of temperature on the defect band photoluminescence (PL) of moderately phosphorous doped amorphous silicon thin films deposited by magnetron sputtering. We have identified two types of recombination processes responsible for the observed temperature dependence of the defect PL band produced by subgap excitation. One of the processes is similar to that observed in intrinsic hydrogenated amorphous silicon and may originate from the recombination of carriers at band tail states and dangling bonds. The donor-defect pairs at nearest neighbor sites may be responsible for the second recombination process.