Influence of SnO2 films with high resistance on the performance of CdTe solar cells

In this paper, we report the SnO2 thin films with high resistance prepared by magnetic reactive sputtering on the transparent conductive glass covered with SnO2:F layers, and study the structural, optical, and electrical properties of the films before and after annealing, as well as the influence of the annealing on the performance of CdTe solar cells. The results have shown that SnO2 thin films almost have the same structure as SnO2:F, and SnO2 high resistance transparent (HRT) insertion layer between transparent conductive oxide (TCO) and CdS affects little on light transmittance. After introducing the HRT layer, the tunneling leakage caused by the pinholes can be avoided, which effectively protects the p-n junction (Wu et al. Proceedings of NCPV program review meeting AIP, New York, 22-26, 2001). Meanwhile, higher parallel resistivity, fill factor (FF), short-wave response, carrier concentration, and lower dark saturation current density have been achieved. As a result, the conversion efficiency is improved by 14.5%, from 10.3% to 11.8%.