Manufacture method for GaInP/GaAs/InGaAsP/InGaAs four-junction cascading solar battery

Abstract

The invention discloses a manufacture method for a GaInP / GaAs / InGaAsP / InGaAs four-junction cascading solar battery. The manufacture method is characterized by comprising the following steps of: taking GaAs as a support substrate, bonding a layer of InP on one face of the support substrate, and respectively growing a GaInP / GaAs double-junction battery in lattice matching with the GaAs on the GaAs substrate and an InGaAsP / InGaAs double-junction battery in lattice matching with InP on the InP layer by utilizing a double-face growing technique, wherein the thickness of the InP is 0.5-10 microns. According to the four-junction cascading solar battery provided by the invention, the consumption of an InP substrate is reduced, and meanwhile, a lattice mismatch problem for growing one-chip and multi-junction cascading solar battery materials is effectively solved; and the four-junction cascading solar battery realizing the high-voltage and low-current outputting is beneficial to improvement of the utilization of sunlight energy.

Description

technical field [0001] The invention belongs to the field of photovoltaics, and in particular relates to a manufacturing method of a GaInP / GaAs / InGaAsP / InGaAs four-junction cascaded solar cell. Background technique [0002] As an ideal green energy material, solar cells have become a research hotspot in various countries. In order to promote the further practical application of solar cells, improving its photoelectric conversion efficiency is an effective means to reduce power generation costs. [0003] The use of sub-cells with different band gaps in series can greatly improve the utilization of sunlight. At present, the system with more research and more mature technology is the GaInP / GaAs / Ge triple junction cell. The highest conversion efficiency achieved so far is 32-33%. However, in the triple-junction cell, the Ge bottom cell covers a wide spectrum, and its short-circuit current is large. In order to achieve current matching with other sub-cells, the utilization rate ...

AI Technical Summary

Problems solved by technology

However, due to the use of lattice mismatch growth, the crystal quality of 1.0eV InGAs is difficult to improve

For example, from the perspective of lattice matching, the bonding of GaInP / GaAs (1.9 / 1.42eV) based on GaAs substrate and InGaAsP / InGaAs (1.05 / 0.74eV) double junction cell of InP substrate is adopted, and conventional wafer bonding is adopted. The technology requires two substrates of GaAs and InP to be grown, and the GaAs-based double-junction cell can be grown by flip-chip and the GaAs substrate is peeled off, but a step-off stripping process is added, which increases the cost of cell manufacturing and the difficulty of the manufacturing process; and adopts mechanical strength Relatively low InP is used as a supporting substrate, which reduces the mechanical strength of the battery, and the price of an InP substrate of the same size is at least three times that of a GaAs substrate, which increases the cost of the battery

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