A kind of preparation method of partial back field n-type solar cell

Abstract

The invention relates to a local back field N type solar cell, a preparation method thereof, a local back field N type solar cell assembly and a local back field N type solar cell system. The preparation method of the local back field N type solar cell includes the following steps that: doping is performed on an N type crystalline silicon base body, barrier layers are grown, and then, a mask which is in an auxiliary grid-shaped pattern and is formed by acid-resisting slurry is printed on the back surface of the N type crystalline silicon base body; the silicon base body is immersed in an acid solution, so that the barrier layer not covered with the mask can be removed; the silicon base body is immersed in an alkaline solution, so that the mask can be removed, and etching is performed on other regions, and an n+ heavy doped region under the mask is retained; and the silicon base body is immersed in the acid solution again, so that the barrier layers left on the silicon base body can be removed; and finally electrodes are prepared, the preparation of the back field N type solar cell is completed. According to the preparation method of the invention, since back surface auxiliary grids only contact with local n+ heavy doped regions, so that contact resistance is low; and regions which do not contact with the back surface auxiliary grids are non-doped regions, so that Auger recombination is low. The prepared cell has high photoelectric conversion efficiency.

Description

technical field [0001] The invention relates to the technical field of solar cells, in particular to a method for preparing a partial back field N-type solar cell. Background technique [0002] A solar cell is a semiconductor device that converts solar energy into electricity. At present, the mainstream products in the industry are P-type crystalline silicon solar cells. The battery process is simple, but it has a light-induced decay effect, that is, the efficiency of the battery will gradually decay with time, which is mainly due to the combination of boron atoms doped into the P-type silicon substrate and oxygen atoms in the substrate. Produces boron-oxygen pair results. Studies have shown that the boron-oxygen pair acts as a carrier trap, reducing the minority carrier lifetime, which leads to the attenuation of the photoelectric conversion efficiency of the battery. Compared with P-type crystalline silicon solar cells, N-type crystalline silicon solar cells have the ad...

AI Technical Summary

Problems solved by technology

The existing technology cannot well solve the contradiction between the fill factor brought by the n+ type doped region on the back surface and the open circuit voltage and short circuit current

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