Electrical modeling of heterojunction silicon solar cells including Indium-Tin-Oxide layers

In this contribution we performed opto-electrical simulations of heterojunction silicon (HJ Si) solar cell with Indium-Tin-Oxide layers included in simulations as front and rear contacts. Two-dimensional numerical simulations using Sentaurus TCAD software were carried out. We studied the effect of defect state density in p- and n-type hydrogenated amorphous silicon layers on device performance. Rigorous analysis revealed mainly a decrease of FF in cases of high levels of defect densities, leading to degradation of conversion efficiency. The increase of defects in p-a-Si proved to be more detrimental than the same increase in n-a-Si, regardless whether the light enters through the p-a-Si or n-a-Si side of the device.