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DOE OSTI · 1603903

Three-Terminal Bipolar Junction Bottom Cell as Simple as PERC: Towards Lean Tandem Cell Processing

Rienacker, M.·Warren, Emily L·Wietler, T. F.·Stradins, Pauls·Tamboli, Adele C·Peibst, R.
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Abstract

Silicon-based tandem cells are a potential upgrade for the dominating PERC technology and can greatly increase the conversion efficiency. A novel approach, the three-terminal (3T) tandem using interdigitated back-contact (IBC) cells, was shown to combine the advantages of four- and two-terminal tandem cells at the expense of a more complex bottom cell fabrication process. In this paper, we propose a simplified and lean PERC-like 3T bipolar junction bottom cell featuring two minority-carrier selective contacts and a single majority-carrier selective contact, and thus resembling a bipolar junction transistor architecture. We present the lean PERC-like fabrication process and explain the working principle by using current-voltage measurements of illuminated 3T IBC cells.

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14 SOLAR ENERGY36 MATERIALS SCIENCE3Tbipolar junction bottom celltandemthree-terminal

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Rienacker, M., Warren, Emily L, Wietler, T. F., Stradins, Pauls, Tamboli, Adele C, Peibst, R.. 2020-02-06. Three-Terminal Bipolar Junction Bottom Cell as Simple as PERC: Towards Lean Tandem Cell Processing. https://doi.org/10.1109/pvsc40753.2019.8980645

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