NREL鉱山研究者が、地球上で使用可能なIII-V族太陽電池の開発に前進を示す(NREL, Mines Researchers Show Advances in Development of III-V Solar Cells for Use on Earth)





ダイナミックハイドライド気相成長法によるAlInPパッシベーションIII-V太陽電池の作製 AlInP-passivated III–V solar cells grown by dynamic hydride vapor-phase epitaxy

Jacob T. Boyer,Kevin L. Schulte,Matthew R. Young,Aaron J. Ptak,John Simon
Progress in Photovoltaics  Published: 02 October 2022


We report the development of AlInP-passivated solar cells grown by dynamic hydride vapor-phase epitaxy (D-HVPE) with AM1.5G efficiencies of 26.0% for single-junction (1J) GaAs cells and 28.0% for GaInP/GaAs (2J) tandems. We compare the device performance of solar cells passivated with AlInP versus control cells passivated with GaInP, which has already enabled near-unity carrier collection in GaAs solar cells. 1J devices passivated with either AlInP or GaInP have an identical open-circuit voltage (VOC) of 1.06 V and long-wavelength current collection near 95%, indicating that both window materials provide a similar degree of passivation. Adding AlInP passivation to each solar cell structure improves the current collection by 1.3 and 1 mA/cm2 for the 1J and 2J, respectively. The AlInP also results in a top cell VOC boost of ~40 mV relative to a tandem device passivated only by a thin, highly doped GaInP emitter. Secondary-ion mass spectrometry measurements indicate that although O and Si both incorporate in the AlInP window, they do not appear in the subsequently grown absorber layers and do not impact its ability to passivate the front surface. We expect that these achievements, along with continued optimization, will enable parity of hydride vapor-phase epitaxy (HVPE)-grown device efficiencies with state-of-the-art devices grown by other epitaxial methods in the near future.

研磨不要で基板を再利用できるスポーリングされたゲルマニウム上に成長した高効率太陽電池 High-Efficiency Solar Cells Grown on Spalled Germanium for Substrate Reuse without Polishing

John S. Mangum,Anthony D. Rice,Jie Chen,Jason Chenenko,Evan W. K. Wong,Anna K. Braun,Steve Johnston,Harvey Guthrey,John F. Geisz,Aaron J. Ptak,Corinne E. Packard
Advanced Energy Materials  Published: 16 June 2022


Radical reduction of III–V device costs requires a multifaceted approach attacking both growth and substrate costs. Implementing device removal and substrate reuse provides an opportunity for substrate cost reduction. Controlled spalling allows removal of thin devices from the expensive substrate; however, the fracture-based process currently generates surfaces with significant morphological changes compared to polished wafers. 49 single junction devices are fabricated across the spalled surface of full 50 mm germanium wafers without chemo-mechanical polishing before epitaxial growth. Device defects are identified and related to morphological spalling defects—arrest lines, gull wings, and river lines—and their impact on cell performance using physical and functional characterization techniques. River line defects have the most consistent and detrimental effect on cell performance. Devices achieve a single junction efficiency above 23% and open-circuit voltage of 1.01 V, demonstrating that spalled germanium does not need to be returned to a pristine, polished state to achieve high-quality device performance.