NRELの改良でIII-V太陽電池の効率が向上(NREL Improvements Boost Efficiency of III-V Solar Cells)


2023-10-25 米国国立再生可能エネルギー研究所(NREL)



III-V族ヘテロ接合太陽電池の性能向上のためのモデリングと設計 Modeling and design of III-V heterojunction solar cells for enhanced performance

Kevin L. Schulte,John Simon,Myles A. Steiner,Aaron J. Ptak,
Cell Reports Physical Science  Published:August 24, 2023


•Computational modeling and experimental testing of rear heterojunction solar cells
•Efficiency is a function of emitter doping and energy band offsets
•Model results inform the development of a 27% efficient GaAs cell grown by HVPE
•Model results developed using III-Vs are potentially applicable to other materials


Heterojunctions can increase the efficiency of solar cell devices relative to homojunctions, but there is a large parameter space with significant tradeoffs that must be considered. Here, we present an experimental and computational study of III-V heterojunction solar cells and show how the emitter doping, emitter band gap, and heteroband offsets impact device efficiency. Efficiency is maximized by pushing the junction depletion region into the wider band gap material while minimizing the effects of heteroband offsets through optimized choice of emitter band gap, emitter electron affinity, and/or emitter doping density. We use these results to guide optimization of devices grown by halide vapor phase epitaxy, achieving 27% efficiency in a GaAs/GaInPAs heterojunction device. We also show that heterojunctions yield proportionally larger efficiency improvements in lower-quality materials. Although the modeling was developed and validated using III-V materials, the results are theoretically applicable to materials systems outside III-Vs.

Graphical abstract

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