Back POLY method of BC battery

Abstract

The invention relates to the technical field of BC batteries, in particular to a back POLY method of a BC battery. The back POLY method of the BC battery comprises a method for producing an N-POLY layer by using PECVD (Plasma Enhanced Chemical Vapor Deposition) equipment and preparing a P-POLY layer by adopting an LPCVD (Low Pressure Chemical Vapor Deposition) method, and adopts the following technical scheme: carrying out double-sided polishing on a silicon wafer, then preparing a polycrystalline silicon layer on the back surface of the silicon wafer by adopting the LPCVD method, carrying out boron diffusion to form the P-POLY layer and carrying out first imaging processing after the preparation is finished, and carrying out second imaging processing after the preparation is finished, carrying out secondary polishing treatment on the steel plate; and preparing the amorphous silicon film on the surface of the silicon wafer subjected to the secondary polishing treatment by adopting PECVD (plasma enhanced chemical vapor deposition) equipment. According to the method, the back POLY method of the BC battery is optimized, the P-POLY is made only by adding LPCVD equipment, and the N-POLY layer is made by using existing PECVD equipment, so that an existing machine can be utilized, and the product technology upgrading cost is reduced.