A crystal silicon solar battery thermal diffusion method for making PN node

Abstract

The invention provides a new method of crystal silicon solaode thermal diffusion to prepare PN knot, the method relates to filed of crystal silicon solaode technique, steps includes: adding step of silicon piece cooling, controlling temperature and time to craftwork of producing PN knot in step (3) of normal crystal silicon solaode, that is cooling before silicon piece departs high temperature diffusion furnace, temperature of the silicon piece in quartz tube is decreased for 200deg.C-300deg.C. Concrete steps are following: a. setting thermal diffusion craftwork parameter to prepare PN knot; b. cooling silicon piece in quartz tube to make temperature of silicon piece 200deg.C-300deg.C lower than diffusion temperature, time of cooling is (10-60) minutes; c. picking up silicon piece from quartz tube. Adopting said new method can decrease heat injury of crystal silicon, decrease heat stress curving or cataclasm, decrease affect of impurity to PN knot, current, voltage, power and photoelectricity conversion efficiency of crystal silicon solaode can be increased, cost of production is decreased.

Description

technical field [0001] The invention relates to the technical field of crystalline silicon solar cells, in particular to a new method for preparing PN junctions by thermal diffusion of crystalline silicon solar cells. Background technique [0002] At present, the common process route for industrial production of crystalline silicon solar cells is: (1) silicon wafer cleaning, (2) removal of silicon wafer damage layer and preparation of suede, (3) thermal diffusion to prepare PN junction, (4) removal of silicon wafer Peripheral PN junction, (5) Clear the oxide layer on the illuminated surface of the silicon wafer, (6) Prepare the anti-reflection film, (7) Screen print the back electrode silver paste, the back electric field aluminum paste and the front electrode silver paste, (8) Aluminum back Field sintering and silver electrode alloy, (9) Test and inspection. In the actual work of preparing PN junctions by thermal diffusion, high-temperature thermal diffusion is generally u...

AI Technical Summary

Problems solved by technology

In the actual work of preparing PN junctions by thermal diffusion, high-temperature thermal diffusion is generally used, but high temperature will cause thermal damage to crystalline silicon, and the huge temperature difference when the high-temperature silicon wafer leaves the quartz tube will cause thermal stress to bend or crack. Impurities in the air will affect the quality of the PN junction, all of which will affect the current, voltage, power and photoelectric conversion efficiency of crystalline silicon solar cells