gainp/gaas/ingaas three-junction solar cell epitaxial structure

Abstract

The invention discloses a GaInP / GaAs / InGaAs triple-junction solar cell epitaxial structure. The epitaxial structure comprises a substrate, a corrosion stripping layer on the substrate, a GaInP first sub-cell on the corrosion stripping layer, a first tunnel junction on the first sub-cell, a GaAs second sub-cell on the first tunnel junction; a lattice transition layer on the second sub-cell, a second tunnel junction on the lattice transition layer and an InGaAs third sub-cell on the second tunnel junction. Materials of the lattice transition layer can be any group-III-V materials of Al InGaAs, GaInP, Al GaInP, GaInPAs, Al GaInAsP and the like with the lattice constant in a range of 0.5656 nm to 0.579 nm and the energy gap Eg larger than 1.4 eV simultaneously. Compared with the prior art, P-type doped lattice transition layer materials replace traditional N-type doped lattice transition layer materials, and growth sequences of the second tunnel junction and the lattice transition layer are changed, accordingly, the line dislocation density of InGaAs materials is decreased, the InGaAs cell open-circuit voltage is increased, and the conversion efficiency of the whole triple-junction solar cell is further improved.

Description

technical field [0001] The invention belongs to the field of epitaxial growth of compound semiconductor thin-film solar cells, and in particular relates to growing a GaInP / GaAs / InGaAs triple-junction high-efficiency solar cell epitaxial structure on a GaAs substrate, which can further improve the photoelectric conversion efficiency of the cell. Background technique [0002] The III-V compound semiconductor multi-junction solar cell is a solar cell with the highest conversion efficiency, and has the advantages of strong high temperature resistance, strong radiation resistance, and good temperature characteristics. In recent years, with the development of concentrated photovoltaic technology, GaAs and related compound III-V solar cells have attracted more and more attention due to their high photoelectric conversion efficiency. Concentrating photovoltaic technology concentrates and concentrates a large area of ​​sunlight at a high rate, and then irradiates it to a small area o...

AI Technical Summary

Problems solved by technology

The growth of InGaAs materials under the condition of lattice mismatch will inevitably produce a large number of linear dislocations, which will significantly reduce the open circuit voltage of InGaAs cells, thereby reducing the overall conversion efficiency of this GaInP / GaAs / InGaAs triple-junction solar cell.

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