Development of a novel CdTe/ZnS/ZnTe heterojunction thin-film solar cells: a numerical approach

Abstract

A novel heterojunction structure of cadmium telluride (CdTe)/zinc sulfide (ZnS)/zinc telluride (ZnTe) for thin-film solar cell (TFSC) applications was investigated numerically by Solar Cell Capacitance Simulator in One Dimension (SCAPS-1D). We made a comparative study on the performance of single-layer of Si/CdTe and multi-layers of Si/CdTe/ZnS/ZnTe structures. The optimum values for the thicknesses of CdTe absorber, ZnS, and ZnTe layers in the cell were found to be 2500, 40, and 80 nm, respectively. In the present work, the conversion efficiency (η) of 21.38% was obtained with open-circuit voltage, Voc = 1.01 V, short-circuit current density, Jsc = 29.32 mA cm−2, and fill-factor, FF = 72.06% in case of multi-layer structure with antireflection coatings (ARCs). The simulation results suggest that the ARC layers presented in this study would be effective to fabricate the high-efficiency solar cells.