Mask structure of copper electroplating grid line for HAC battery and preparation method of mask structure

Abstract

The invention discloses a mask structure of a copper electroplating grid line for an HAC battery. According to the invention, silicon nitride or silicon oxide or silicon nitride-silicon oxide composite films are prepared on the surfaces of TCO layers at the two sides of a battery piece to serve as masks of a copper electroplating grid line, and the masks are left on the surface of the battery piece after the copper electroplating grid line is prepared and are not removed; and the refractive indexes of the mask and the TCO are matched with each other. The invention further discloses a preparation method of the mask of the copper electroplating grid line for the HAC battery. ITO thin films are deposited on the two surfaces of the crystalline silicon wafer deposited with the amorphous siliconrespectively to serve as TCO layers; silicon nitride or silicon oxide or silicon nitride-silicon oxide composite films are deposited on the surfaces of the two ITO films by adopting a plate type PECVD method or a hot filament CVD method to serve as mask layers of the copper electroplating grid line, and the masks are left on the surfaces of the battery piece after the copper electroplating grid line is prepared without removing the masks. According to the method, the mask of the copper-plated grid line is prepared by a method shorter than a photoetching process, and the obtained mask is reserved on the surface of the cell after the grid line is prepared, so the anti-reflection effect of TCO is improved.

Description

technical field [0001] The invention belongs to the field of solar cells and semiconductor devices, and relates to the technology of crystalline silicon solar cells, in particular to a mask structure of copper electroplating grid lines for HAC cells and a preparation method thereof. Background technique [0002] At present, there are two main technical routes for metal grid lines of amorphous silicon / crystalline silicon heterojunction solar cells (hereinafter referred to as HAC). Using low-temperature silver paste as raw material, the preparation technology route is simple, easy to master, less process, low process cost, but consumes a lot of silver paste; the second is to use photolithography combined with electroplating technology to prepare copper grid lines, this technology uses copper and chemical solution As the main raw material, photoresist is required in the photolithography process, and there are many processes such as mask preparation, exposure, and glue removal. ...

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Problems solved by technology

[0004] In addition, the transparent conductive oxide layer (transparent conductive oxide hereinafter referred to as TCO) on the surface of HAC solar cells is mainly made of indium oxide as the main material, such as tin-doped indium trioxide (hereinafter referred to as ITO), which must take into account both conductivity and anti-reflection effects , so that the anti-reflection effect cannot be optimized, which also limits the improvement of the performance of HAC solar cells. If the anti-reflection effect can be improved by the method of composite film layer, it is also very meaningful to improve the performance of HAC solar cells.

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