Numerical investigation of silicon heterojunction solar cell with zinc selenide as electron-selective and nickel oxide as hole-selective contacts

Abstract

In this simulation study, we proposed a new silicon heterojunction solar cell (n-ZnSe/p-Si/p-NiOX) as a potential candidate for photovoltaic application. In this device, a thin layer of zinc selenide has been proposed as an electron-selective contact while nickel oxide as a hole-selective contact. A one-dimensional solar cell capacitance simulator has been used to investigate the performance of the proposed device by varying the various physical parameters like defects densities at both the interfaces (n-ZnSe/p-Si and p-Si/p-NiOX), absorber layer doping density, absorber layer defects densities, absorber layer thickness, capture cross-sections of the carriers, operating temperature, series resistance, shunt resistance, and hole-selective contact. A comparison between n-ZnSe/p-Si & n-ZnSe/p-Si/p-NiOX heterojunction solar cells has also been performed. In our study, we have found that the higher concentration of interface defect density at the n-ZnSe/p-Si interface deteriorates the performance of the device substantially more than the p-Si/p-NiOX interface. Further, the presence of hole-selective contact improves the open-circuit voltage as well as the efficiency of the device considerably. In this work, the best simulated open-circuit voltage is 744 mV and efficiency is 19.39%. These optimized parameters owing to provide a new path to fabricate a highly efficient silicon heterojunction solar cells.