A method for smoothing the surface of copper-catalyzed etching textured silicon wafers

Abstract

The invention relates to a method for smoothly treating the surface of a copper-catalyzed etching velvet-making silicon wafer, belonging to the technical field of surface velvet-making of crystallinesilicon in the solar cell industry. The invention cleans the silicon wafer of the diamond wire cutting and removes the oxide layer. At room temperature ~ 95 degree centigrade, that silicon wafer afterthe oxide lay removal treatment is placed in HF-Metal copper salt-H2O2 etch solution is etched for 1-600 min, then immerse in nitric acid solution for 1-100 min, then immersed in HF solution for 1-100 min, and then cleaned with deionized water to obtain inverted pyramid textured silicon wafer; A smooth invert pyramid structure woven silicon wafer is obtained by smoothing the inverted pyramid structure woven silicon wafer; The method of smoothing treatment is to adopt smoothing treatment system method and / or ultrasonic treatment method. The method of the invention can realize the inverted pyramid smooth pile-making structure obtained by the low-cost MCCE method.

Description

technical field [0001] The invention relates to a method for smoothing the surface of a silicon chip made of texture by copper-catalyzed etching, and belongs to the technical field of texture of the surface of crystalline silicon in the solar cell industry. Background technique [0002] At present, with the widespread promotion of diamond wire slicing technology, and in view of the failure of the traditional mortar cutting method to use acid texturing on diamond wire cut polysilicon wafers, it is urgent to find a feasible and low-cost texturing method. Metal Catalyzed Etching Texturing (MCCE) is expected to break through the challenges of efficient texturing on the surface of diamond wire-cut silicon wafers, and has attracted much attention. In view of the high cost of using noble metals (Ag, Au, Pt, etc.) Not only does it have a good effect of removing line marks, but also obtains an excellent light trapping effect. At the same time, it has the advantages of lower cost and...

AI Technical Summary

Problems solved by technology

[0004] The present invention aims at the problem that the surface of the diamond wire-cut silicon wafer is processed by MCCE method and the sharp structure existing on the inverted pyramid is introduced into the surface, which makes it difficult to effectively cover the anti-reflection film, the minority carrier life is too low, and the series resistance is too large, which leads to the decrease of the efficiency of the battery module. The problem is to provide a method for smoothing the surface of silicon wafers made of copper-catalyzed etching, that is, using a low-cost metal copper-catalyzed chemical etching method to realize the controllable preparation of large-scale inverted pyramid arrays on the silicon-based surface, and obtain Smooth inverted pyramid structure textured silicon wafer; the micro-surface structure of the silicon wafer is smooth and has no sharp structure, which can remove the recombination center, improve the minority carrier lifetime, solve the problems of poor passivation, and effectively improve the efficiency of the battery

Images