Influence of Characteristic Energies and Charge Carriers Mobility on the Performance of a HIT Solar Cell

Abstract

In this article, two factors that limit the performance of HIT solar cells (Heterojunction with Intrinsic Thin layer) based on amorphous silicon / crystalline silicon are studied. First, we study the influence of the valence band tail width (characteristic energy ED) and the conduction band tail width (characteristic energy EA) of hydrogenated amorphous silicon [1]. Then we analyze the effect of electrons mobility μn and holes mobility μp in the emitter of the structure ITO/p-a-Si:H /i-pmSi:H /n-c-Si/Al. Our results show that a decrease of ED in the p-a-Si: H layer decreases the donors density of states in the gap, as well as holes recombination in this layer. However, no amelioration is observed when EA decreases. Furthermore, we show that increasing the mobility of charge carriers μn and μp, enhance the performance of the studied solar cells.