Wet surface processing technique used for manufacturing high efficiency crystalline silicon solar cells

Abstract

The invention relates to a wet surface processing technique used for manufacturing high efficiency crystalline silicon solar cells. The surface wet processing technique comprises the following steps of (1) pre-washing a silicon chip; (2) removing damage and thinning the silicon chip, wherein the upper and lower surfaces of the silicon chip are in a polishing shape; (3) coating protection: depositing a protective film on a single surface of the silicon chip; (4) surface structuralizing: obtaining a pyramid suede structure with a depth of 4-10 microns for the surface of the silicon chip which has no protective film, and meanwhile keeping a plane state for the surface of the other side of the silicon chip which has the protective film; (5) removing the protective film; (6) performing RCA washing, and (7) enhancing and optimizing for the surface appearance and forming a wet passivated surface. With the adoption of the wet surface processing method provided by the invention, the requirement on single-sided cleaning and texturing of the substrate of the thin silicon chip in the manufacturing process of high efficiency solar cells can be simply satisfied; the cleaning process quality and the battery efficiency and yield can be effectively improved; and moreover, no additional relevant cleaning equipment is required, and thus, the process cost is saved.

Description

technical field [0001] The invention relates to the field of manufacturing high-efficiency solar cells using crystalline silicon materials as substrates, in particular to a surface wet treatment process for making high-efficiency crystalline silicon solar cells. Background technique [0002] Generally, back-passivated solar cells with selective emitters have attracted much research attention because of their structural advantages and high conversion efficiency. This battery structure has two main features: First, a heavy diffusion field with relatively high doping concentration and deep junction area is generated in the area below and near where the front electrode will be formed, while a low doping concentration is generated at other positions on the front surface. And the light diffusion area with shallow junction depth can effectively reduce the contact resistance and increase the short-wave response of the battery to improve the photoelectric conversion efficiency; Impr...

AI Technical Summary

Problems solved by technology

In actual production, it is often necessary to introduce a single-side polishing cleaning machine into the battery manufacturing process, which greatly increases the cost per watt of the battery. In addition, the silicon wafers that have become thinner after the previous process are processed by a single Surface polishing treatment will also make it easier to control the fragmentation rate

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