Back contact solar cell, preparation method therefor, and photovoltaic module

A photovoltaic module, comprising:

• at least two back contact solar cells, wherein each back contact solar cell comprises:
• a substrate, having a first surface and a second surface opposite to the first surface, wherein the substrate has an edge;
• and
• a first doped layer and a second doped layer, alternately arranged on the first surface, wherein a doping type of the first doped layer is opposite to a doping type of the second doped layer, and wherein the doping type of the second doped layer is the same as a doping type of the substrate, wherein a first isolation region is provided between the edge and a boundary of the first doped layer adjacent to the edge, a second isolation region is provided between the edge and a boundary of the second doped layer adjacent to the edge, wherein a width of at least a portion of the first isolation region is greater than a width of at least a portion of the second isolation region;
• and
• a plurality of electrical connectors, wherein the plurality of electrical connectors connect the at least two back contact solar cells.

A preparation method for a back contact solar cell, comprising:

• providing a substrate, the substrate having a first surface and a second surface opposite to the first surface, the first surface having an edge;
• forming a first doped layer on the first surface of the substrate and patterning the first doped layer, a doping type of the first doped layer being opposite to a doping type of the substrate;
• forming a second doped layer on the first surface of the substrate and patterning the second doped layer, a doping type of the second doped layer being opposite to the doping type of the first doped layer;
• and
• forming a first isolation region through the first doped layer along a thickness direction of the substrate when patterning the first doped layer or the second doped layer, the first isolation region spacing the first doped layer from the edge;
• and forming a second isolation region through the second doped layer along the thickness direction of the substrate, the second isolation region spacing the second doped layer from the edge, wherein a width of the first isolation region is greater than a width of the second isolation region.