Microwave near-field probes for photovoltaic applications

Abstract

The photoresponse of three different photovoltaic Cu(In, Ga)Se2 (CIGS) samples as well as GaAs and silicon bulk samples is measured using near-field scanning microwave microscopy (NSMM). Modeling predicts light-dependent conductivity values for bulk samples, as well as a preliminary understanding of more complicated multilayer photovoltaics. The spectral dependence of CIGS samples is probed at 405, 635, 808 and 980 nm wavelengths. In addition, we present two-dimensional raster scans that may reveal grain-boundary effects under illumination.