Preparation method of solar cell for reutilizing diffusion oxide layer

Abstract

The invention relates to a preparation method of a solar cell for reutilizing a diffusion oxide layer. The method comprises the following steps of: not removing a silicon oxide layer (such as BSG (Boron Silicate Glass) and PSG (Phosphosilicate Glass)) formed by diffusion on a front face immediately but plating a layer of film on the oxide layer after a diffusion process is completed to form a double-layer film for serving as a mask for quickly removing back face junctions subsequently and for use in a procedure for making a back face electric field by back diffusion; and removing the film and the silicon oxide layer on the front face, and a silicon oxide layer on the back face together with hydrofluoric acid in a post cleaning procedure. Due to the adoption of the method, back junctions formed by diffusion can be removed quickly, the production process flow is optimized, the cell producing and manufacturing time is shortened greatly, and mass production is available.

Description

technical field [0001] The invention relates to a production process of a high-efficiency single-crystal silicon solar cell, in particular to a production process of a high-efficiency single-crystal silicon solar cell. Background technique [0002] Compared with P-type batteries, N-type batteries have the characteristics of less efficiency loss due to light-induced attenuation, and are more resistant to pollution by metal impurities. Existing high-efficiency cells are all realized on N-type substrates. The boron diffusion temperature of N-type B-junction cells is high, the time is long, and the depth of the formed back junction is relatively deep. It is difficult to remove it in the post-cleaning steps of ordinary production lines. At the same time, in the existing silicon cell production process, immediately remove the phosphosilicate glass or borosilicate glass and cut the edge after the diffusion, and when phosphorus diffusion or Peng diffusion is required to control the...

AI Technical Summary

Problems solved by technology

The boron diffusion temperature of N-type B-junction cells is high, the time is long, and the formed back junction is deep. It is difficult to remove it in the post-cleaning steps of ordinary production lines.

At the same time, in the existing silicon cell production process, immediately remove the phosphosilicate glass or borosilicate glass and cut the edge after the diffusion, and when the phosphorus diffusion or Peng diffusion is required to control the back electric field, it will be additionally used The method of growing SiO2 by thermal oxidation or depositing SiNx by PECVD process adds a layer of mask on the front side, the production process steps are complicated, and the production and manufacturing time is long, especially the processing time of SiO2 grown by thermal oxidation method is generally 2 to 3 hours