Method for manufacturing selective texturing heterojunction solar cell

Abstract

The invention discloses a method for manufacturing a selective texturing heterojunction solar cell, which comprises the following steps of: pre-cleaning a monocrystalline silicon wafer, removing damages, manufacturing a delay layer in a selective texturing area on the surface of the monocrystalline silicon wafer by using a delay material, texturing the monocrystalline silicon wafer, dissolving the delay layer in the selective texturing area by using texturing liquid in the texturing process, and then, preparing a texturing solution in the selective texturing area; and enabling the suede of the selective texturing area to be later than the delay-layer-free area, forming at least two suede microstructures in different position areas on the monocrystalline silicon wafer at one time, and depositing and printing grid lines after texturing to obtain the battery. Different textured microstructures can be formed on the same surface of the same monocrystalline silicon wafer, so that the heterojunction solar cell can obtain the optimal antireflection effect, and meanwhile, the amorphous silicon passivation quality can be greatly enhanced; the delay layer can be arranged differently, different suede microstructures can be formed at a time, the delay material of the delay layer can be directly removed in the texturing process, the production process is reduced, and the cost is reduced.

Description

technical field [0001] The invention relates to a method for manufacturing a heterojunction solar cell, in particular to a method for selectively texturizing a heterojunction solar cell. Background technique [0002] Amorphous silicon / crystalline silicon heterojunction solar cells use [100] oriented monocrystalline silicon wafers, and then use alkaline solution to make texture, so as to obtain a texture with uniform and dense micron-scale pyramids on the surface, which can obtain good anti-reflection effect and increase The incidence of light can effectively increase the short-circuit current of the battery, and then use plasma-enhanced chemical vapor deposition (PECVD) to grow a layer of intrinsic amorphous silicon layer on the surface to passivate the surface, and then the front and back Deposit an n-type amorphous silicon layer and a p-type amorphous silicon layer respectively, and then deposit a transparent conductive film layer on the front and back sides, print grid li...

AI Technical Summary

Problems solved by technology

It can be known from theoretical calculations: the more slender the pyramid, that is, the larger the ratio of height / bottom surface area, the easier the incident light is trapped between the pyramids and absorbed by the battery, and the anti-reflection effect is better; and the more slender the pyramid The sharper the edges and corners at the sharp points, edges, and valleys, this leads to the epitaxial growth of the amorphous silicon passivation film deposited and grown in these places. These epitaxially grown films have a higher defect state density, which greatly increases The recombination probability of photogenerated carriers at the amorphous silicon / crystalline silicon interface, resulting in a significant drop in open circuit voltage

The pyramid texture produced on the surface of the silicon wafer by the existing technology has a single texture microstructure, and there is often a contradiction between the anti-reflection effect of the pyramid texture and the deposition quality of amorphous silicon. The sharper the surface microstructure, the better the anti-reflection effect. Well, the flatter the surface microstructure, the better the deposition quality of amorphous silicon, and the better the passivation, which makes it difficult for the surface structure of existing heterojunction solar cells to balance the anti-reflection effect and passivation quality

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