Novel DBR structure for lattice-mismatching multi-junction solar cell

Abstract

The invention discloses a novel DBR structure for a lattice-mismatching multi-junction solar cell, and the novel DBR structure is a GaInNAs/AlGaInAs periodic structure superimposed on a lattice gradual change buffer layer, and is made of two alloy materials: GaInNAs and AlGaInAs. GaInAs subcells are stacked on the GaInNAs/AlGaInAs periodic structure, and the GaInNAs refractive index of the GaInNAs/AlGaInAs periodic structure is higher than that of AlGaInAs, and there is lattice mismatching between GaInNAs and AlGaInAs and between GaInAs and a base region material GaInAs of the GaInAs subcells,wherein the mismatching degree is not greater than 3%. The strain compensation structure facilitates the stress release and dislocation slip. The structure provided by the invention can reduce the defect density in an epitaxial layer introduced by the mismatching, improves the material quality, can improve the anti-irradiation performance of the GaInAs subcells, adds the overall short-circuit current, open circuit voltage, filling factor and other technical indexes of the cells, and improves the overall photoelectric conversion of the cells.

Description

technical field [0001] The invention relates to the technical field of solar photovoltaic power generation, in particular to a novel DBR structure applied to lattice-mismatched multi-junction solar cells. Background technique [0002] With the development of modern industrial technology, the world-wide energy crisis and environmental pollution problems have become increasingly prominent. As a clean and renewable energy, solar energy has gradually attracted the attention of various countries. From the perspective of the development history of photovoltaic power generation technology, solar cells can be roughly divided into three categories: the first generation of crystalline silicon solar cells, the second generation of thin-film solar cells and the third generation of gallium arsenide multi-junction solar cells. At present, the conversion efficiency of commercial monocrystalline silicon cells is about 16% to 20%, and that of polycrystalline silicon cells is about 14% to 16%...

AI Technical Summary

Problems solved by technology

However, there is still a threading dislocation density that cannot be ignored in the top sub-cell. In order to meet the high requirements of the development of aerospace technology, the crystal quality and radiation resistance of the material need to be further improved.

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