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DOE OSTI · 2424768

Electrical passivation of III-V multijunction solar cells with luminescent coupling effect

Yu Jeco-Espaldon, Bernice Mae·Tamaki, Ryo·Giteau, Maxime·Xu, Hao·Ahsan, Nazmul·King, Richard R.·Okada, Yoshitaka
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Abstract

Perimeter recombination is one of the causes identified for having a nonuniform luminescent coupling effect in III-V multijunction solar cells. A potential solution could be the electrical passivation of the multijunction solar cell perimeter. To test this hypothesis, electrical passivation of InGaP/GaAs/Ge 3-junction solar cells was done by the atomic layer deposition of thin Al2O3 films. Further, perimeter passivation of a 3-junction solar cell relatively increased current collection measured at luminescent coupling and direct subcell excitation by as much as 11.4% and 29.8%, respectively. Meanwhile, the current homogeneity improved relatively by as much as 7.9% after electrical passivation. At 1-sun global standard illumination (AM 1.5G), 0.2% absolute conversion efficiency increase was achieved. Therefore, electrical passivation of fully working III-V multijunction solar cells is a non-invasive, post-treatment process that can recover losses due to surface defects caused by oxidation.

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14 SOLAR ENERGYAtomic layer depositionCurrent mappingLuminescence couplingMultijunction solar cellPassivationRecombination

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Yu Jeco-Espaldon, Bernice Mae, Tamaki, Ryo, Giteau, Maxime, Xu, Hao, Ahsan, Nazmul, King, Richard R., Okada, Yoshitaka. 2022-10-17. Electrical passivation of III-V multijunction solar cells with luminescent coupling effect. https://doi.org/10.1016/j.solmat.2022.112045

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