Method for preparing solar cell, and solar cell

A method for preparing a solar cell, comprising:

• providing a substrate having a first surface and a second surface opposite to the first surface;
• forming a doped layer over the first surface of the substrate and a first passivation layer over the doped layer, wherein the doped layer forms a PN junction with the substrate;
• forming a second passivation layer on the second surface;
• performing a sintering process on a surface of the first passivation layer away from the substrate to form a plurality of first grid line electrodes arranged at intervals on the surface of the first passivation layer;
• performing a sintering process on a surface of the second passivation layer away from the substrate to form a plurality of second grid line electrodes arranged at intervals on the surface of the second passivation layer;
• and
• performing laser processing on the plurality of first grid line electrodes and regions adjacent the plurality of first grid line electrodes, wherein a reverse current is applied between the plurality of first grid line electrodes and the plurality of second grid line electrodes to reverse bias the PN junction during the laser processing, and wherein the each of the regions adjacent the plurality of first gridline electrodes is a region within a preset distance from an edge of one of the plurality of first grid line electrodes.