Investigation Of Crystalline Silicon Solar Cells Towards High Efficiency

The fabrication methods of high efficient solar cells are summarized in this paper, especially summarizing SE solar cells. The characters of the selective emitter solar cells'structure is proved to be an effective way to improve the solar cell conversion efficiency in the course of deeply analyzing on its advantages. And using domestic mono-crystalline silicon wafers, and based on the screen printed C-Si solar cells industrial processes, through adding one process of ink-jet print printing high phosphorus paste before POCl3 diffusion, a kind of solar cells are fabricated. After electrical chemical testing and I-V testing, these solar cells are proved to have the typical selective emitter structure and high performance. Their conversion efficiencies are about 0.2-0.3 percentage higher than that of the conventional BSF solar cells, and their spectral responses are also better than that of BSF solar cells during the short wavelength area. All these prove this method can be brought into the industrial utilization.In order to improve the fabrications and enhance the performance of the solar cells, we summarize the important technologies of rear surface passivation, and analyze micro-smic mechanism of the intrinsic silicon thin film and its developing condition. These thin films which are deposited in our lab using HWCVD prove the equipment has superiorities rather than other deposition equipments, including higher efficiency, lower deposition temperature and none ion bombarding. Also based on the conventional line, we fabricated solar cells with new passivation structure-- double-sided passivation with hydrogenated intrinsic silicon thin film and silicon nitride. According to the testing results by I-V and WT-2000 testing equipments, these solar cells have lower density of Recombination via defects, higher minority lifetime and higher electrical efficiency.