Solar cell emitter region fabrication using self-aligned implant and cap

摘要

Methods of fabricating solar cell emitter regions using self-aligned implant and cap, and the resulting solar cells, are described. In an example, a method of fabricating an emitter region of a solar cell involves forming a silicon layer above a substrate. The method also involves implanting, through a stencil mask, dopant impurity atoms in the silicon layer to form implanted regions of the silicon layer with adjacent non-implanted regions. The method also involves forming, through the stencil mask, a capping layer on and substantially in alignment with the implanted regions of the silicon layer. The method also involves removing the non-implanted regions of the silicon layer, wherein the capping layer protects the implanted regions of the silicon layer during the removing. The method also involves annealing the implanted regions of the silicon layer to form doped polycrystalline silicon emitter regions.

主权项

1. A method of fabricating an emitter region of a solar cell, the method comprising:
forming a silicon layer above a substrate, the silicon layer distinct from the substrate; implanting, through a stencil mask, dopant impurity atoms in the silicon layer to form implanted regions of the silicon layer with adjacent non-implanted regions; forming, through the stencil mask, a capping layer on and substantially in alignment with the implanted regions of the silicon layer; removing the non-implanted regions of the silicon layer, wherein the capping layer protects the implanted regions of the silicon layer during the removing, and wherein removing the non-implanted region of the silicon layer comprises removing only the non-implanted region of the silicon layer and retaining the implanted regions of the silicon layer; annealing the implanted regions of the silicon layer to form doped polycrystalline silicon emitter regions from the implanted regions of the silicon layer; and forming conductive contacts on the doped polycrystalline silicon emitter regions.