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DOE OSTI · 1845667

Progress in three-terminal heterojunction bipolar transistor solar cells

Antolín, Elisa·Zehender, Marius H.·Svatek, Simon A.·Steiner, Myles A.·Martínez, Mario·García, Iván·García‐Linares, Pablo·Warren, Emily L.·Tamboli, Adele C.·Martí, Antonio
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Abstract

Conventional solar cells, including multijunction solar cells, are based on pn junctions as building blocks. In contrast, the three-terminal heterojunction bipolar transistor solar cell (3T-HBTSC) explores the use of a bipolar transistor structure to build a solar cell. The limiting efficiency of this transistor structure equals that of a double-junction solar cell. However, since the 3T-HBTSC does not require tunnel junctions, its minimal structure has only three semiconductor layers, while the minimal structure of a double junction solar cell has six. This work reviews the operation principles of this solar cell and the steps carried out towards its practical implementation. Experimental results on a GaInP/GaAs HBTSC prototype with bottom interdigitated contacts are presented.

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14 SOLAR ENERGYIII-V materialbase transport factorbottom interdigitated contactemitter injection efficiencyheterojunction bipolar transistor solar cellmultijunction solar celltandem solar cell

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Antolín, Elisa, Zehender, Marius H., Svatek, Simon A., Steiner, Myles A., Martínez, Mario, García, Iván, García‐Linares, Pablo, Warren, Emily L., Tamboli, Adele C., Martí, Antonio. 2022-01-26. Progress in three-terminal heterojunction bipolar transistor solar cells. https://doi.org/10.1002/pip.3536

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