Tube type PERC single-sided solar cell, preparation method thereof and special equipment thereof

Abstract

The invention discloses a tube type PERC single-sided solar cell, which comprises a main silver back gate, an all-aluminum back electric field, a back-side composite film, a P-type silicon, an N-type emitting electrode, a front-side passivation film and a positive silver electrode. The back-side composite film is composed of one or more selected from an aluminum oxide film, a silicon dioxide film, a silicon oxynitride film and a silicon nitride film and is deposited at the back of a silicon chip by adopting tube type PECVD equipment. The tube type PECVD equipment comprises four gas pipelines of silane, ammonia, trimethyl aluminum and laughing gas. The appliance of the tube type PECVD equipment, used for loading and unloading silicon chips, is a graphite boat. The depth of a sticking point groove of the graphite boat is 0. 5-1 mm. The invention also discloses a preparation method and special equipment of the tube type PERC single-sided solar cell. According to the invention, the photoelectric conversion efficiency is high. Meanwhile, the appearance yield and the EL yield are high. The problems of scratching, winding and plating can be solved.

Description

technical field [0001] The invention relates to the field of solar cells, in particular to a tubular PERC single-sided solar cell, a preparation method and special equipment for the tubular PERC single-sided solar cell. Background technique [0002] Crystalline silicon solar cell is a device that effectively absorbs solar radiation energy and converts light energy into electrical energy by using the photovoltaic effect. Under the action, holes flow from the N region to the P region, electrons flow from the P region to the N region, and a current is formed after the circuit is turned on. [0003] Traditional crystalline silicon solar cells basically only use front passivation technology, depositing a layer of silicon nitride on the front of the silicon wafer by PECVD to reduce the recombination rate of minority carriers on the front surface, which can greatly increase the open circuit voltage and short circuit of crystalline silicon solar cells current, thereby improving the...

AI Technical Summary

Problems solved by technology

Tubular PECVD coating has two disadvantages: 1. During the insertion process, the silicon wafer will rub against the graphite boat wall, resulting in scratches on the side of the silicon wafer next to the graphite boat wall

2. During the deposition process, due to the inevitable gap between the silicon wafer and the graphite boat wall, especially the large gap at the stuck point, the process gas will diffuse to the other side of the silicon wafer and form a film on the other side. , that is, winding plating, and the winding plating at the stuck point is more serious

2. There is no coating film on the back of the conventional battery, and the film layer around the edge of the back side is relatively thin, which does not look obvious and does not affect the appearance yield

[0009] However, using tubular PECVD to make the back film of the PERC battery, scratches and wrapping seriously affect the qualified rate of the finished battery. The problems are: 1. During the deposition process, the back film will wrap around the edge of the front side, because the PERC battery is Double-sided coating, the thickness of the coating on the front edge is thicker, resulting in boat marks and color difference on the front edge of the battery, which affects the appearance yield

2. During the process of inserting the wafer into the graphite boat, the front side of the silicon wafer will touch the graphite boat wall, and the PN junction on the front side will be scratched, resulting in scratches in the EL test and affecting the electrical performance of the battery

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