Review—Process Research on Intrinsic Passivation Layer for Heterojunction Solar Cells

On top of a crystalline silicon wafer, heterojunction solar cells have a thin layer of amorphous silicon (a-Si) placed on it. The efficiency of heterojunction solar cells can be increased by decreasing the electron complex loss by adding an inherent passivation layer to a monocrystalline silicon (c-Si) substrate. In this study, we examine the development of the intrinsic passivation layer deposition technique on c-Si substrates over the previous ten years by several research teams. First, a description of the structure, benefits, and passivation of heterojunction solar cells is given. Following that, the impact of modifying process variables on the functionality of the passivation layer and cell efficiency is explored in terms of the passivation material, hydrogen dilution ratio, substrate temperature, and post-deposition annealing. Last but not least, the ideal process parameters are summed up and potential future research areas are predicted. One of the best ways to increase the conversion efficiency of heterojunction solar cells is through surface passivation technology, and future domestic and international research will focus heavily on the process technology of its intrinsic passivation layer.