Double-sided heterojunction solar cell and preparation method

Abstract

The invention discloses a double-sided heterojunction solar cell and a preparation method. The solar cell comprises a silicon slice base layer; the back surface of the silicon slice base layer is provided with an intrinsic layer, a heavily doped BSF layer and a back electrode from inside to outside in sequence; tilted slots are arranged on the front face of the silicon slice base layer in parallel; intrinsic silicon films and p-type silicon film layers are respectively arranged on the inclined planes of the slots; the p-type silicon film layer is provided with a transparent conductive film used as a positive electrode; the transparent conductive film and the bottom surfaces of the slots are respectively provided with film anti-reflection layers; the surface of the silicon slice base layer is further provided with a silver paste layer which is electrically connected with the transparent conductive film. As the electrode is arranged in a tilting way in the invention, and as the p-type silicon film layers are arranged on the inclined planes of the slots, the p-type silicon film layers are in tilting contact with the electrode; the advantage that the vertical projection area of the inclination planes of the slots is small is fully utilized, thus, the shading loss of the overall solar cell by the positive electrode is reduced, the spectral response of the solar cell is effectively improved and the improvement of the overall performance of the cell is favored.

Description

technical field [0001] The invention relates to the technical field of solar cells, in particular to a double-sided heterojunction solar cell and a preparation method thereof. Background technique [0002] Silicon heterojunction solar cells use amorphous silicon thin films deposited on crystalline silicon substrates as emitters, but doped amorphous silicon emitter thin films can absorb part of the visible light, which affects the effective use of light by the base substrate. It is beneficial to the short-wave response of the cell and limits the conversion efficiency of the solar cell. It can be seen that reducing the light absorption of the emissive layer becomes an effective way to improve the conversion efficiency of the heterojunction solar cell. At present, wide bandgap silicon films are mainly used as the emission layer, but the cost of complex doping process is high, and the electrical properties of wide bandgap doped films cannot be guaranteed. [0003] For heterojun...

AI Technical Summary

Problems solved by technology

[0004] Another major factor affecting heterojunction solar cells is interface state recombination. The emitter layer of a traditional silicon heterojunction solar cell covers the entire area of ​​a single crystal silicon substrate, and the contact interface in the junction region is relatively large. However, the thin film / crystalline The problem of silicon interface contact has always been the bottleneck of the conversion efficiency of heterojunction cells

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