A kind of selective emitter n-type crystalline silicon solar cell and its preparation method

Abstract

The invention discloses an n-type crystalline silicon solar cell with a selective emitter and a preparation method thereof. The method comprises: depositing a layer of boron-rich doping source on a specific pattern area of ​​a silicon wafer; The borosilicate glass layer on the back of the silicon wafer is removed on one side while the borosilicate glass layer on the front is retained; the boron emitters on the back and edge of the silicon wafer are removed and textured again; the phosphorus on the back of the silicon wafer is diffused , and form a selective back field; clean and remove the borosilicate glass layer on the front and the phosphosilicate glass layer on the back, deposit an aluminum oxide silicon nitride anti-reflection passivation film on the front, and deposit a silicon nitride passivation film on the back; screen print the front electrode and back electrode. The present invention can achieve selective boron emitter through one-step diffusion on the basis of no additional boron source, greatly reduce the recombination of the metal contact area, increase the open circuit voltage of the solar cell, improve the short-wave response of the cell, and increase the short-circuit current, thereby effectively Improve the photoelectric conversion efficiency of solar cells.

Description

technical field [0001] The invention belongs to the field of photovoltaic technology, and in particular relates to an n-type crystalline silicon solar cell with a selective emitter and a preparation method thereof. Background technique [0002] The constant pursuit of higher photoelectric conversion efficiency and lower manufacturing cost is the eternal theme of the photovoltaic industry. At present, p-type crystalline silicon solar cells occupy the absolute share of the crystalline silicon market, but n-type crystalline silicon wafers have the advantages of high minority carrier lifetime and no light-induced attenuation compared with conventional p-type crystalline silicon wafers, and have higher-end efficiency improvement space. The prepared n-type crystalline silicon solar cell and component have good weak light response, low temperature coefficient and higher reliability. As the efficiency advantages of n-type crystalline silicon solar cells become more and more obvious...

AI Technical Summary

Problems solved by technology

[0003] One of the cores of the preparation method of n-type crystalline silicon solar cells is the preparation of boron emitters. At present, the method of BBR3 liquid source diffusion is widely used in the market. The boron emitters prepared by this method have difficulty in controlling the square resistance uniformity and the metal electrode contact area. The problem of high recombination leads to low open circuit voltage and poor fill factor of the battery, which greatly limits the improvement of n-type solar cell efficiency, and it is difficult to use the etching or laser commonly used in p-type crystalline silicon solar cells for boron emitters. doping by way of selective emitter

Images