AFORS-HET simulation study of HIT solar cells: Significance of inversion layer

Abstract

The energy band diagram of the HIT solar cell obtained using AFORS-HET simulations reveals that a p-type inversion layer is induced in the n-type c-Si near the front hetero-interface. The HIT solar cell actually behaves like a pseudo p-n homojunction solar cell, in which the p-type inversion layer acts as the cell emitter and controls the performance of the solar cell. The formation of the inversion layer is controlled by the Fermi level of the p-Si:H layer, which is adjustable by varying its doping level. The study also suggests that the work function of the front TCO layer should be keep as high as possible for achieving high conversion efficiency.