Additive and method for texturing of diamond wire cut polycrystalline silicon chip

Abstract

The invention relates to an additive and a method for texturing of a diamond wire cut polycrystalline silicon chip. The additive is prepared from components as follows: acetic acid, triethanolamine, sodium dodecyl benzene sulfonate, polyethylene glycol, triamine citrate, perfluoropolyether, hydrofluoric acid and water in the mole ratio being (15-25):(10-25):(1-10):(15-25):(1-10):(1-10):(1-5):(2-100). The texturing additive can better refine the inside structure of an etch pit of the silicon chip to form more and smaller micro etch pits, the surface porosity is higher, the surface etch pit holes are denser, the size of the etch pits is reduced, small hole structures are produced on the edge and at the bottom of the etch pits, and the reflectivity of the silicon chip is greatly reduced.

Description

Technical field [0001] The invention relates to the technical field of solar cells, in particular to an additive and a method for making texturing of polycrystalline silicon wafers by diamond wire cutting. Background technique [0002] Solar power generation is an important part of new energy. Silicon wafers account for the largest proportion of the cost structure of crystalline silicon solar cells. Reducing the cost of silicon wafers is essential for achieving photovoltaic parity on the grid. Based on the advantages of low silicon consumption per unit capacity, high cutting efficiency, low cost of auxiliary materials and ability to cut thin silicon wafers, diamond wire-cut monocrystalline silicon wafers have basically replaced the traditional mortar cutting process, greatly enhancing the cost competition of monocrystalline silicon wafers In 2016, the market share of monocrystalline silicon solar cells rebounded to more than 25%. In this context, the polysilicon industry is also...

AI Technical Summary

Problems solved by technology

However, as a new type of crystalline silicon wafer cutting technology, diamond wire cutting technology also has certain technical problems to be solved.

The surface damage of polycrystalline silicon wafers cut by diamond wire is less, and tear-shaped line marks are produced on the surface of polycrystalline silicon wafers. As a result, it is difficult to obtain ideal texture in the process of texturing using the existing acid texturing technology based on silicon wafer surface damage and preferential isotropic etching. surface, so that the photoelectric conversion efficiency of crystalline silicon cells is affected, which seriously restricts its industrial application.