Two-dimensional modeling of CdZnTe/Si based dual and triple junction solar cells

Abstract

Based on Crosslight APSYS, we have made 2D simulation of dual and triple junction solar cells based on CdZnTe and CdTe material system on Si substrate with tunnel junctions. The basic physical quantities like band diagram, optical absorption and generation for these solar cells, and external quantum efficiency for individual subcell junctions of triple junction solar cells are obtained. Current matching analyses and multi-sun concentration simulation are also performed. The modeling shows efficiency 28.85% (one sun AM1.5G) for CdZnTe/Si dual junction solar cells and efficiency 34.92% (one sun AM1.5G) and maximum 39.09% (multi-sun concentration around 500-700 suns) for CdZnTe/CdTe/Si triple junction solar cells. The presented results indicate that the dual and triple junction solar cells with II-VI CdZnTe and CdTe on Si can achieve efficiency comparable to those III-V based compound on Ge substrate.