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DOE OSTI · 1604609

Combinatorial Study of MZO Emitters for CdTe-Based Solar Cells

Samoilenko, Yegor·Yeung, Gavin·Zakutayev, Andriy·Reese, Matthew O·Wolden, Colin A.
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Abstract

Precise band alignment at the front interface of CdTe-based solar cells is necessary to reduce photoexcited charge carrier recombination and to enable higher energy conversion efficiencies. Magnesium zinc oxide is not only transparent but also offers the ability to tune the conduction band offset with CdTe at the front of the device stack. In this work, we describe reactive sputtering of Mg 1-x Zn x O using metal targets and its application in CdTe photovoltaics. Combinatorial libraries of Mg 1-x Zn x O were created to tune the conduction band alignment for the optimal performance of CdTe solar cells. Band gap variation of more than 0.4 eV is achieved across a 3-inch substrate. Kelvin probe measurements demonstrate variance of work function across the substrate. Device performance is optimized at band gaps of 3.5 eV for the CdTe device processing conditions employed in this study.

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14 SOLAR ENERGY42 ENGINEERINGband alignmentbuffer layercadmium tellurideKelvin probemagnesium zinc oxide

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Samoilenko, Yegor, Yeung, Gavin, Zakutayev, Andriy, Reese, Matthew O, Wolden, Colin A.. 2020-02-06. Combinatorial Study of MZO Emitters for CdTe-Based Solar Cells. https://doi.org/10.1109/pvsc40753.2019.8980695

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