Five-knot cascade photovoltaic cell with antireflection film

Abstract

The invention discloses a five-knot cascade photovoltaic cell with an antireflection film. The five-knot cascade photovoltaic cell is structurally characterized in that, a bottom electrode is disposed on the lower surface of an InP substrate, a GaAs sub-cell, a GaInAs sub-cell and a GaInP sub-cell are sequentially disposed on the upper surface of the Inp substrate, the GaInP sub-cell is provided with a strain compensation GaAsP / GaInAs superlattice sub-cell. A GaInP sub-cell is disposed on the strain compensation GaAsP / GaInAs superlattice sub-cell. A first antireflection layer is disposed between the GaInAs sub-cell and the GaInP sub-cell. A second antireflection layer and a third antireflection layer are disposed between the strain compensation GaAsP / GaInAs superlattice sub-cell and the GaInP sub-cell disposed on the strain compensation GaAsP / GaInAs superlattice sub-cell. A fourth antireflection layer, a fifth antireflection layer and a sixth antireflection layer are disposed on the GaInP sub-cell disposed on the strain compensation GaAsP / GaInAs superlattice sub-cell, and a top electrode is formed on the fourth antireflection layer.

Description

technical field [0001] The invention relates to the technical field of semiconductor optoelectronics, in particular to a five-junction cascade photovoltaic cell with an antireflection film. Background technique [0002] Photovoltaic cells are optoelectronic devices that convert light energy into electrical energy. For photovoltaic cells, single-junction photovoltaic cells can only cover and utilize sunlight in a certain wavelength range. Generally, a variety of semiconductor materials with different band gaps are combined to form a multi-junction photovoltaic cell. [0003] At present, in lattice-matched GaInP / GaAs / Ge triple-junction photovoltaic cells, the photoelectric conversion efficiency can reach a maximum of 32% under no concentration conditions. In this triple-junction cell, the Ge cell covers a wide spectrum, and its short-circuit current can be up to twice that of the other two-junction cells. Due to the restriction of the triple-junction cell being connected in s...

AI Technical Summary

Problems solved by technology

GaInP / (In)GaAs / InGaAsN / Ge four-crystal lattice-matched cells can theoretically obtain high conversion efficiency, but limited by the difficulty of reducing the defect density of InGaAsN materials, this four-junction cell poses great challenges to material growth.

GaInP / (In)GaAs / InGaAsN / GaAs / Ge five-crystal lattice-matched cells can also theoretically achieve high conversion efficiency, but the current problems are similar to those of four-junction photovoltaic cells

[0004] Moreover, during the photoconversion process of the photovoltaic cell, the loss of reflection reduces the number of incident photons per unit area of ​​the photovoltaic cell, resulting in a decrease in the current density of the photovoltaic cell, thereby affecting the energy conversion efficiency of the battery. In order to improve the photoelectric conversion efficiency of the battery, the battery should be reduced Reflection loss of surface light, increased light transmission

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