Enhanced Current Collection in 1.7 eV GaInAsP Solar Cells Grown on GaAs by Metalorganic Vapor Phase Epitaxy
Enhanced Current Collection in 1.7 eV GaInAsP Solar Cells Grown on GaAs by Metalorganic Vapor Phase Epitaxy
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通过金属有机气相外延在 GaAs 上生长的 1.7 eV GaInAsP 太阳能电池增强电流收集
DOI:
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发表时间:
2017
影响因子:
3
通讯作者:
M. Steiner
中科院分区:
文献类型:
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作者:
N. Jain;J. Geisz;R. France;A. Norman;M. Steiner
Quaternary GaInAsP solar cells with a bandgap of ∼1.7 eV offer an attractive Al-free alternative to AlGaAs solar cells for integration in next generation of III–V multijunction solar cells with five or more junctions. Development of a high quality 1.7 eV solar cell is also highly sought for III–V/Si tandem solar cells. In this work, we systematically investigate the impact of varying base thicknesses and doping concentrations on the carrier collection and performance of 1.7 eV GaInAsP solar cells. The photoresponse of these cells is found to be very sensitive to p-type zinc doping concentration in the base layer. Prototype 1.7 eV GaInAsP n-i-p solar cell designs are demonstrated that leverage enhanced depletion width as an effective method to achieve peak quantum efficiency exceeding 90%. We also show the importance of optimal i-layer thickness as a critical parameter to reduce the drop in fill-factor (FF) due to field-aided collection. Furthermore, we demonstrate substantial improvement in the cell performance when the GaInAsP base layer is grown at 650 °C instead of 600 °C. The best GaInAsP solar cell (<italic>E<sub>g</sub></italic> ∼ 1.65 eV) in this study achieved <italic>J</italic><sub>SC</sub> of 21.1 mA/cm<sup>2</sup>, <italic>V</italic><sub>OC</sub> of 1.18 V, FF of 83.8%, and an efficiency of 20.8 ± 1% under AM1.5D spectrum (21.5 ± 1% under AM1.5G spectrum). These results highlight the potential of Al-free GaInAsP solar cells for integration in the next generation of III–V multijunction solar cells.