Extraction of local thin-film solar cell parameters by bias-dependent IR-LBIC

Abstract

A bias-dependent Infrared Light Beam Induced Current (IR-LBIC) analysis was performed on polycrystalline silicon (poly-Si) thin-film solar cells on glass. The local electrical characteristics of the absorber layer can be extracted from a simple theoretical model based on the assumption of the diffusion length smaller than the absorber layer thickness. The depletion depth and spatially resolved doping concentration were obtained from the results. Furthermore, the diffusion length in the absorber layer of the thin-film solar cell can also be extracted spatially. This is possible due to the low absorption coefficient of poly-Si in the IR range.