Method for preparing solar battery by adopting paraffin wax external-frame masking method

Abstract

The invention discloses a method for preparing a solar battery by adopting a paraffin wax external-frame masking method. The method comprises the following steps: (1) forming a smooth trap surface on a velvet silicon wafer; (2) forming PN junctions by diffusing and doping on a velvet surface; (3) printing a paraffin wax mask having a masking function on a diffusing surface; (4) covering a water film on the silicon wafer covered with the mask; (5) utilizing chemical liquid to remove the redundant PN junctions on the periphery and rear surface of the silicon wafer; (6) utilizing the chemical liquid to etch the surface of the silicon wafer; (7) removing the paraffin wax mask; (8) removing phosphorus silicon glass; (9) plating a silicon nitride film; (10) printing a rear electrode and a rear field; (11) printing a silver electrode in the corresponding position of the paraffin wax mask; and (12) sintering and testing the electrical property. According to the method provided by the invention, when the solar battery is prepared by adopting the paraffin wax external-frame masking method, the problem of influence on silicon wafer quality caused by poor water film covering is effectively solved, and meanwhile, the printing position of the silver electrode is accurate and aligned, so that the conversion efficiency of the battery cell is increased.

Description

technical field [0001] The invention relates to the field of preparation of solar cells, in particular to a method for preparing solar cells by using a paraffin outer frame mask method. Background technique [0002] In the process step of printing the paraffin mask, the style of the printed paraffin graphics is determined by the customer's needs, and the set graphic parameters are input into the paraffin printer, and the machine will automatically print out the corresponding paraffin mask. In the process step of chemical liquid removal of excess PN junctions around and on the back of the silicon wafer, it is necessary to completely cover the printing paraffin surface with a layer of water film to ensure that the entire surface of the silicon wafer will not be etched by the process Corrosion of acid gas in the medium, because paraffin is a hydrophobic substance, when the paraffin is printed on the silicon wafer and then covered with water film, the water film is often corrode...

AI Technical Summary

Problems solved by technology

[0006] The invention provides a method for preparing solar cells by using a paraffin outer frame mask method, which solves the problem of poor water film coverage in the past when the paraffin mask method is used to prepare solar cells, which leads to the PN junction on the periphery and back of the silicon chip being covered. Acid gas corrosion in the process, which affects the quality of silicon wafers

Images