Front composite film for improving edge winding and plating color difference of tubular PERC solar cell

Abstract

The invention discloses a front composite film for improving the edge winding and plating color difference of a tubular PERC solar cell, and the front composite film sequentially comprises a SiNx:Hy layer, a SiOxNy layer and a SiOx layer. The SiNx:Hy layer at least comprises five layers of SiNx:Hy with different refractive indexes and thicknesses which are respectively a first SiNx:Hy layer, a second SiNx:Hy layer, a third SiNx:Hy layer, a fourth SiNx:Hy layer and a fifth SiNx:Hy layer, and the SiOxNy layers at least comprise 2-3 SiOxNy layers with different refractive indexes and thicknesse,wherein the SiOx layer at least comprises one SiOx layer with different refractive indexes and thicknesses. By adopting the method, the front edge winding and plating color difference caused by adopting tubular plasma equipment to prepare the back passivation film in the PERC battery manufacturing process can be effectively improved, and the appearance uniformity of the photovoltaic module is improved.

Description

technical field [0001] The invention relates to the field of solar cell manufacturing, in particular to a front composite film for improving the color difference of the edge wrapping of tubular PERC solar cells. Background technique [0002] A crystalline silicon solar cell is a semiconductor optoelectronic device that converts sunlight into electrical energy. The basic principle is to use semiconductor technology to create a PN junction. Under the action of the built-in potential field, the photogenerated electrons and holes are separated, and move to the N-type side and the P-type side in opposite directions respectively, forming a photogenerated voltage, which is drawn out through the electrodes to form a current on the load circuit. [0003] The P-type monocrystalline PERC solar cell, which has become the mainstream technology in the photovoltaic industry, compared with the traditional all-aluminum back field monocrystalline solar cell that adopts the aluminum back field...

AI Technical Summary

Problems solved by technology

[0004] However, due to the current AlOx / SiOxNy / SiNx:Hy multilayer film structure on the back, the AlOx / SiOxNy / SiNx:Hy layer or SiOxNy / SiNx:Hy layer or SiNx:Hy layer often uses tubular PECVD (Plasma Enhanced Chemical Vapor Deposition) equipment Preparation, because the tubular PECVD equipment uses graphite boats as the silicon wafer supporting device, and the silicon wafer is vertically attached to the tubular plasma coating equipment. During the process of plating the back passivation film, part of the reaction gas will migrate to the edge of the front surface. Regional reactions generate SiOxNy, SiNx:Hy winding coatings, and after using the existing technology to coat the positive film, the film thickness of the surrounding coating will cause the film thickness in the edge area of ​​the positive film to be greater than that in the central area. The difference in film thickness will cause the color difference in the appearance of the component, and this color difference is called "edge-wound plating chromatic aberration"

[0005] The existing technology uses 1-3 layers of SiNx:Hy film as the front passivation and anti-reflection film, which cannot effectively solve the problem of uneven color difference in the appearance of tubular PERC solar cells packaged into photovoltaic modules

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