A kind of wet etching equipment and process

Abstract

The invention discloses a wet etching device which comprises an etching groove and a plurality of rolling shafts used for supporting a silicon wafer to be etched. The rolling shafts are parallelly arranged in the etching groove and are supported through a plurality of supports, and the supports are arranged perpendicular to the rolling shafts. The rolling shafts are at least divided into sections, and one support is arranged at one connection position of the two sections and is higher than other supports. According to the design, a preset included angle exists between the silicon wafer to be etched and an etching liquid face, in an etching process, the liquid face tensile force of etching liquid can be used for enabling the etching liquid to the adhered to the back face and the side face of the silicon wafer to be etched, the distance between the back face of the silicon wafer to be etched and the etching liquid face is overall increased, and therefore the etching liquid is not prone to flowing to the front face of the silicon wafer to be etched, an etching edge is further reduced, the effective light receiving area of a solar cell is enlarged, and the generating capacity is increased. In addition, the invention further discloses a wet etching process.

Description

technical field [0001] The invention relates to the technical field of solar cell manufacturing, in particular to a wet etching device. The present invention also relates to a wet etching process using the above wet etching equipment. Background technique [0002] In the process of manufacturing solar cells, it is necessary to diffuse and form junctions on the surface of silicon wafers. In this process, phosphorus is inevitably diffused on the surface (including the edge) of silicon wafers, which will cause a short circuit. Therefore, in the process of making solar cells , in order to ensure the insulation of the front and back of the solar cell, after the phosphorus diffusion process, the silicon wafer needs to be etched. [0003] At present, the wet etching process is mostly used in the production process of solar cells. The principle of the wet etching process is: use hydrofluoric acid, nitric acid and sulfuric acid in accordance with a predetermined ratio with a mixed a...

AI Technical Summary

Problems solved by technology

In the current common structure, there is a gap between the bracket and the roller, such as figure 1 As shown, there is an arc-shaped groove on the bracket 1', and the roller 2' is placed in the arc-shaped groove of the bracket 1', but there is a certain distance between the outer peripheral surface of the roller 2' and the bottom wall of the arc-shaped groove, During the etching process, the roller 2' is prone to sink under the tension of the etchant, resulting in a reverse liquid phenomenon, which causes the etchant to corrode the front side of the silicon wafer to be etched, which further leads to enlarged or irregular etching edges and reduces solar energy. The effective light-receiving area of ​​the battery

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