A deep semiconductor defect with continuously variable activation energy and capture cross section

Abstract

A deep level with a continuously varying activation energy and capture cross section has been observed in CdS/CdTe thin-film solar cells. Given that the activation energy and capture cross section of a level are usually considered to be a unique identifier or signature for a particular deep level, this has important implications for the application of deep-level transient spectroscopy and related techniques for the characterization of deep levels in this and similar systems. We believe this phenomenon explains the well-known but poorly understood efficacy of CdCl2 treatment for CdS/CdTe thin solar cells.