Repair process and preparation process of tubular perc solar cells

Abstract

The invention discloses repair technology of a tubular PERC solar cell. The repair technology is set after annealing of a silicon wafer and before film coating of a back face of the silicon wafer. The repair technology comprises the following steps: (1) a semi-finished silicon wafer which stays over 4 hours after the annealing and before the film coating is placed into a repair furnace, nitrogen having a flow rate of 5-10slm is introduced into the repair furnace to achieve self-cleaning, and inlet time of the nitrogen is 1-5min; (2) nitrogen having a flow rate of 5-20slm is introduced to blow and sweep dust on the silicon wafer; (3) temperature of the repair furnace is raised from room temperature to 500-650 DEG C, and nitrogen having a flow rate of 1-5slm is introduced at the same time; and (4) the temperature of the repair furnace is kept at 500-650 DEG C for 5-30min, and nitrogen having a flow rate of 5-20slm is introduced at the same time. Correspondingly, the invention further discloses a preparation technology of the tubular PERC solar cell. Through adoption of the repair technology and the preparation technology, the problem of efficiency reduction brought by too long semi-finished product stay time is solved, and the EL yield rate is improved.

Description

technical field [0001] The invention relates to the field of PERC solar cells, in particular to a repairing process of a tubular PERC solar cell and a preparation process of the tubular PERC solar cell. Background technique [0002] In the manufacturing process, each process often has process problems or downtime caused by machine failures, which will cause the semi-finished products in the previous process to stay. The manufacturing process of tubular PERC cell is: texturing, diffusion, etching, annealing, back coating, positive coating, laser, screen printing, sintering. The inventors found in experiments that the conversion efficiency of the battery will drop significantly if the interval from annealing to the back coating exceeds 4 hours, and the longer the interval, the greater the drop in efficiency, and the maximum drop in efficiency can reach more than 0.2%. Theoretically, the longer the interval, the silicon wafer will absorb moisture in the air, significantly redu...

AI Technical Summary

Problems solved by technology

[0009] The technical problem to be solved by the present invention is to provide a repair process for tubular PERC solar cells, to solve the problem of efficiency drop caused by the long residence time of semi-finished products, and to improve the yield rate of EL

[0010] The technical problem to be solved by the present invention is to provide a preparation process for tubular PERC solar cells, which can solve the problem of efficiency drop caused by the long residence time of semi-finished products, and improve the yield rate of EL

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