A preparation method of n-type crystalline silicon heterojunction solar cell with full back electrode

Abstract

The invention discloses a preparation method of all-back electrode N-type crystalline silicon heterojunction solar cells. The preparation method comprises the steps of preparing a nano textured surface, an N+ type phosphorus shallow diffusion crystalline silicon layer and a SiOx passivation / SiNx antireflection layer on the front surface of an N-type substrate; preparing an N++ type phosphorus deep diffusion crystalline silicon layer on the back surface of the N-type substrate, adopting corrosive printing paste to achieve local corrosion of the N++ type phosphorus deep diffusion crystalline silicon layer, depositing an intrinsic non-crystalline silicon film layer and a p-type non-crystalline silicon film layer sequentially, and removing intrinsic non-crystalline silicon and p-type non-crystalline silicon on the surface layer of the area of the N++ type phosphorus deep diffusion crystalline silicon layer; then, sputtering a transparent conducting film layer, and separating a P area and an N area on the back surface of the N-type substrate through lasers; finally, carrying out electrode printing and low temperature sintering. According to the preparation method, all metal electrodes are transferred to the back surfaces of the cells and no electrodes exist on the light-receiving surfaces, so that the production cost of modules and the combination loss of the cells are lowered, the optical loss and the resistance are greatly reduced, and the efficiency is greatly improved.

Description

technical field [0001] The invention relates to a method for preparing a solar cell structure, in particular to a method for preparing a full-back electrode N-type crystalline silicon heterojunction solar cell. Background technique [0002] With the continuous development of crystalline silicon solar cell technology, great achievements have been made in the research of high-efficiency monocrystalline silicon solar cell. Based on the N-type silicon substrate full back electrode (IBC) battery structure developed by Sunpower in the United States, the grid electrodes are all designed on the back of the battery, and the positive and negative electrodes are arranged in a crossed manner. The mass production efficiency can reach 23%, and the highest efficiency in the laboratory can reach 24.2. %. In April 2014, Panasonic announced that by combining heterojunction technology (HIT) and back contact electrode technology (IBC), its newly developed commercial size (143.7cm 2 ) The phot...

AI Technical Summary

Problems solved by technology

The most deadly problem is that in the CN102214719A patent "the P-type region forms n + a-si / i-a-si / N-c-si / N + "Back side N in c-si / i-a-si / p-a-si heterojunction structure" + The existence of "c-si diffused crystal silicon layer" leads to an increase in the potential barrier, which greatly reduces the open circuit voltage, so it is necessary to remove the P-type region of the N + Diffusion layer; while the "front surface n" of the N-type region in the CN102185030A patent + "Amorphous silicon film / N-type silicon substrate / N-region electrode" also makes it difficult for electrons to cross the potential barrier to reach the N-region electrode

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