Alkaline polishing method during production of passivated emitter rear contact (PERC) crystalline silicon solar cell

Abstract

The invention belongs to a manufacturing technique of a solar cell, and relates to an alkaline polishing method during production of a passivated emitter rear contact (PERC) crystalline silicon solar cell. The method comprises the following steps of carrying out conventional processes of etching, diffusion and groove etching on a single-silicon wafer to remove positive-negative (PN) junctions at an edge and a back surface and plating of a silicon nitride film on a front surface by plasma enhanced chemical vapor deposition (PECVD), etching to remove silicon nitride plated on the back surface and at the edge in a rolling way by a belt driving way, and then carrying out polishing processing on the back surface through an alkaline groove; and depositing an aluminum oxide plated thin film on the back surface by an atomic layer, and carrying out conventional processes of laser grooving, metal paste silk-screen printing on the front surface and the back surface and sintering to prepare a PERC battery piece. The alkaline polishing process is integrated into the traditional PERC battery production process, the problems of complicated production process during the current introduction process of alkaline polishing, poor controllability, poor back surface passivation effect caused by plating a film layer on the front surface in a rolling way and the like are solved, so that the production the PERC battery based on alkaline polishing can meet the requirement of yield better.

Description

technical field [0001] The invention belongs to the manufacturing technology of solar cells, and relates to an alkali polishing method in the production of PERC crystalline silicon solar cells. Background technique [0002] With the continuous improvement of crystalline silicon solar cell technology, the mass production conversion efficiency of monocrystalline silicon solar cells with traditional structure has reached 19.2%, and the mass production conversion efficiency of polycrystalline silicon solar cells has reached 17.8%. There is not much room for improvement in the efficiency of cells with traditional structures, and the improvement of cell efficiency must rely on the development of crystalline silicon solar cells with new structures. In the current high-efficiency silicon-based cell technology, since the passivated emitter and rear surface cell (PERC cell) moves the process of improving cell efficiency to the back of the cell, it is compatible with other high-efficie...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide an alkali polishing method that can use the alkali polishing process in the production of PERC crystalline silicon solar cells in the existing PERC cell production process, so that it can improve the complex production process in the current alkali polishing process. , Defects of poor controllability, to solve the problems of poor passivation effect on the back surface caused by the winding plating of the front film layer