Method for carrying out wet-method phosphorous diffusion and texturing on substrate and acid solution for texturing

Abstract

The invention relates to a method for manufacturing a PN junction by carrying out wet-method chemical phosphorous diffusion on a substrate and texturing the substrate, mainly comprising the following steps of: (1) carrying out wet treatment on the substrate by using phosphoric acid; (2) transferring the substrate into a heating furnace for phosphorous diffusion, wherein the temperature inside the heating furnace is 800-900 DEG C, and the heating time is 20-30 minutes; (3) texturing the substrate by adopting an acid solution, wherein the acid solution is a mixed solution of hydrofluoric acid, hydrogen nitrate, phosphoric acid and a surface active agent; and (4) finally cleaning the substrate by using an alkali solution and deionized water, and drying. By means of the method disclosed by the invention, the single-surface diffusion and the texturing of the polycrystalline silicon substrate become easy and feasible, and the production quantity of high-quality PN junction substrates (such as solar cell substrates) through uninterrupted continuous production is greatly improved; and the invention has the advantages of simpleness, high efficiency, low cost and no toxicity.

Description

technical field [0001] The invention relates to a method of applying chemical wet treatment to diffuse and texture semiconductor silicon elements such as solar cell substrates, flat panel display substrates or film substrates, especially in the single-sided continuous online production of large-scale substrates. A method for wet phosphorus diffusion and texturing of substrates and an acid solution for texturing. Background technique [0002] Silicon wafers are the carrier of solar cells, and the quality of silicon wafers directly determines the conversion efficiency of solar cells. Texturing the surface of the silicon wafer can improve the absorption of light, thereby converting more electricity. There are many methods for making polycrystalline silicon wafers, and the common method is acid or alkali solution wet method. Among them, the acid solution has various formulations, and the chemical liquid used is usually a mixture of hydrofluoric acid, nitric acid, phosphoric ac...

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Problems solved by technology

[0005] However, this phosphorus diffusion has the following disadvantages: 1. very long heat treatment; 2. excessive wafer handling; 3. use of toxic chemicals (POCL 3 ); 4. Intermittent production

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