The Study Of Stack Passivation Of Polycrystalline Silicon Solar Cells And Etching Of The Back Of The Pn Junction In The Industrial Production

The use of fossil fuels exacerbates the deterioration of the environmental issues, ready to come out of a variety of green and new energy. Solar energy as a clean renewable energy, people scramble for it.Polycrystalline silicon solar cells studied in this thesis compared with the mono-crystalline silicon solar cells, lower production costs, especially in advanced silicon nitride passivation and gettering after all aspects of the energy conversion efficiency characteristics with monocrystalline silicon solar cells are relatively close. Industrial production focus on the economic benefit. This paper focuses on the industrial production of polycrystalline silicon solar cells passivated research, experiments were performed in the production line, large quantities of experimental data provide an important reference for the production process.In this thesis, the tube PECVD prepared SiNxHy membrane SiNxOy film laminated coating on polycrystalline silicon passivation.First, use industrial tube PECVD equipment preparing SiNxHy film and compare the multilayer and monolayer antireflection. The results showed that the best multilayer is three-layer film, and its reflection rate of5.7, the reflectivity of the monolayer up to7.4. Tracking a large number of experimental data, the efficiency of three-layer film increased by0.12percent than the monolayer.Second, adjust the three-layer film deposition of NH3:SiH4, compare the refractive index, the minority carrier lifetime and its electrical performance parameters. The results show that with increasing silane, short-circuit current was significantly upward trend; best passivation of NH3:of SiH4flow ratio is3900:980.Third, increase the airflow source of industrial tube PECVD equipment nitrous oxide, prepare SiNxOy film and study the impact of various process parameters on the film color. Gas mixture of nitrous oxide and silane deposition of silicon surface, compare the deposition time, silane, and laughter flow ratio on the electrical performance parameters. The results showed that the best passivation effect, three-film deposition time of85s,355s,220s, the first layer of silane, ammonia was4.5of SiH4: N2O=300:3550, solar cell efficiency of0.2%to0.3%increase. On the basis of the best combination, fine-tuning the inner layer thickness and on the electrical performance parameters, find the best inner layer thickness of55nm.Fourth, during the study of etching the back of p-n junction, we use a mask wet etching technology. Use ink made from the front of the mask to protect silicon nitride film etching methods to remove the back junction. The results showed that, etching the back of p-n junction experimental group0.05A, short-circuit current of the experimental group than the normal process to enhance efficiency of0.02%.