Process for preparing back-polished polysilicon solar cells by slurry etching

Abstract

The invention discloses a technological method for preparing a polycrystalline silicon solar cell with a polished reverse side through a slurry corrosion method. The reverse side polishing technology and the edge etching technology are integrated, and the defects that in the prior art, reverse side polishing is complex in technology and equipment, and high in production cost are overcome. The technological method for preparing the polycrystalline silicon solar cell with the polished reverse side through the slurry corrosion method mainly comprises the cleaning and texturing step, the diffusion step, the printing or adhesive dispensing or rotary coating corrosive slurry step, the heating step, the cleaning step, the PECVD step, the silk-screen printing step and the sintering step. According to the technological method for preparing the polycrystalline silicon solar cell with polished reverse side through the slurry corrosion method, reverse side polishing and edge etching are accomplished in one step, the number of technological steps is reduced, production cost is reduced, consumption of chemicals and consumption of gas are greatly reduced, and pollution is reduced.

Description

technical field [0001] The invention relates to the field of preparation of solar cells, in particular to a production process for preparing back-polished polycrystalline silicon solar cells by a slurry etching method. Background technique [0002] In the conventional production process of polycrystalline silicon solar cells, there is no special treatment process on the back of the silicon wafer, and a pit-like suede structure similar to the front is formed on the back. This suede structure is not conducive to the subsequent screen printing of aluminum paste and Silicon contacts, and because the textured structure has light trapping properties, the long-wavelength light passing through the silicon wafer cannot be reflected and reused, further reducing the light utilization rate of the cell. [0003] Based on the above reasons, people began to study the treatment of the backside of the silicon wafer, and finally found that the backside polishing has a good effect. The batter...

AI Technical Summary

Problems solved by technology

One is polishing before texturing. This method needs to use silicon nitride to protect the front surface. The process is relatively complicated and it is difficult to be used in mass production; the other is polishing after diffusion. The process is very easy to cause damage to the PN junction on the front of the silicon wafer, and the process window is very narrow. At present, only a small number of companies are conducting experiments and have not put it into mass production.

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