• Journal of Infrared and Millimeter Waves
  • Vol. 40, Issue 1, 7 (2021)
Hong-Bo LU1、2、3, Xin-Yi LI2、*, Ge LI2, Wei ZHANG2, Shu-Hong HU1, Ning DAI1、*, and Gui-Ting YANG2
Author Affiliations
  • 1State Key Laboratory of Infrared Physics,Shanghai Institute of Technology Physics of the Chinese Academy of Sciences,Shanghai 200083,China
  • 2State Key Laboratory of Space Power-sources,Shanghai Institute of Space Power-sources,Shanghai 200245,China
  • 3University of Chinese Academy of Sciences,Beijing 100049,China
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    DOI: 10.11972/j.issn.1001-9014.2021.01.002 Cite this Article
    Hong-Bo LU, Xin-Yi LI, Ge LI, Wei ZHANG, Shu-Hong HU, Ning DAI, Gui-Ting YANG. Reducing Voc loss in InGaAsP/InGaAs dual-junction solar cells[J]. Journal of Infrared and Millimeter Waves, 2021, 40(1): 7 Copy Citation Text show less

    Abstract

    Smaller Voc of 1.0 eV/0.75 eV InGaAsP/InGaAs double-junction solar cell(DJSC) than the Voc sum of individual subcells has been observed, and there is little information of the origin of such Voc loss and how to minimize it. In this paper, it is disclosed that the dominant mechanism of minority-carrier transport at back-surface-field(BSF)/base interface of the bottom subcell is thermionic emission, instead of defect-induced recombination, which is in contrast to previous reports. It also shows that both InP and InAlAs cannot prevent the zinc diffusion effectively. In addition, intermixing of major III-V element occurs as a result of increasing thermal treatment. To suppress the above negative effects, an initial novel InP/InAlAs superlattice(SL) BSF layer is then proposed and employed in bottom InGaAs subcell. The Voc of fabricated cells reach 997.5 mV, and a reduction of 30 mV in Voc loss without lost of Jsc, compared with the results of conventional InP BSF configuration, is achieved. It would benefit the overall Voc for further four-junction solar cells.

    Introduction

    ReferenceMethodBandgapIllumination

    Jsc

    (mA/cm2)

    Voc

    (mV)

    Woc

    (mV)

    Oshima [2]MBE1.0/0.71AM1.5G13.15701140
    Wu [3]MBE1.05/0.73AM1.5G16.1830950
    Zhao [4]MOVPE1.07/0.74AM1.5D10.2977833

    Table 1. Previous reported results for InGaAsP/InGaAs DJSC

    Hong-Bo LU, Xin-Yi LI, Ge LI, Wei ZHANG, Shu-Hong HU, Ning DAI, Gui-Ting YANG. Reducing Voc loss in InGaAsP/InGaAs dual-junction solar cells[J]. Journal of Infrared and Millimeter Waves, 2021, 40(1): 7
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