Post produced velvet production process of solar cell

Abstract

The invention relates to a production method of a crystalline silicon solar cell, in particular to a post-etching production process of a solar cell. The post-etching production process comprises the following steps: a silicon chip is made into a finished cell after the processes of washing, diffusion, etching, removing phosphor silicate glass, carving edges, plating silicon nitride, anti-reflective coating, printing a back electrode, printing an aluminum back surface field, printing a front electrode and sintering in sequence, and the etching process follows the diffusion process. After the selective diffusion, the silicon chip forms a high doped region and a low doped region, the cross-sectional shape of the high doped region is expected to have consistent width of the top and bottom cross-sections in a perfect condition, however, in the practical production, the cross section of the high doped region is wide at the top and is narrow at the bottom and takes a funnel shape, so after the diffusion is finished, the etching process is carried out, in the process of etching, a thin layer on the surface of the silicon chip is removed, therefore, the thickness of the corresponding high doped region is decreased, and the cross section of the high doped region approximates to the perfect condition of consistent top and bottom width at the moment. The solar cell produced at last has higher conversion efficiency.

Description

technical field [0001] The invention relates to a production method of crystalline silicon solar cells, in particular to a post-texturing production process of solar cells. Background technique [0002] Crystalline silicon solar cells occupy more than 90% of the photovoltaic market. How to further improve efficiency and reduce costs is the basic goal of the research field of crystalline silicon solar cells at home and abroad. [0003] Realizing selective emitter structure on silicon wafer is one of the methods to realize high efficiency of p-n crystalline silicon solar cells. The so-called selective emitter structure has two characteristics: 1) a highly doped deep diffusion region is formed under and near the electrode gate line; 2) a low doped shallow diffusion region is formed in other regions. The key to realizing the selective emitter structure is how to form the two regions mentioned above. There are many ways to realize the selective emission region, the most common ...

AI Technical Summary

Problems solved by technology

However, these methods are too complicated for solar cell manufacturing and can only be applied in laboratories or small-scale production, which is difficult to promote in the industrial production of conventional cells.

In recent years, there has also been a method of using screen-printed phosphorous paste to realize selective emission regions, but due to problems such as pollution caused by screen printing, this method has not been widely used.

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