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DOE OSTI · 1888614

Quantifying Bulk and Surface Recombination in CdTe Solar Cells Using Time-Resolved Terahertz Spectroscopy

Taheri, Mohammad M.·Truong, Triet M.·Fields, Shannon·Shafarman, William N.·McCandless, Brian E.·Baxter, Jason B.
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Abstract

Understanding the nature of recombination mechanisms is essential for higher power conversion efficiency in photovoltaic (PV) devices. Here we use a combination of time-resolved terahertz spectroscopy and numerical modeling to determine the bulk Shockley-Read-Hall lifetime and interface and back surface recombination velocities in CdTe thin film stacks. Furthermore, the measurement was facilitated by fabricating wire-grid device structures using conventional laser scribing. Evaluation of a glass/FTO/SnO2/CdS/CdTe stack treated with CdCl2 allowed separation of the CdTe absorber bulk lifetime, 1.6 ns, from the back surface recombination velocity, ~6x10 4 cm/s, and indicated that CdTe/CdS interface recombination velocity had no significant impact on carrier dynamics.

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14 SOLAR ENERGY36 MATERIALS SCIENCE47 OTHER INSTRUMENTATIONcadmium telluridecarrier dynamicsphotovoltaic cellssemiconductor materialsthin film devices

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Taheri, Mohammad M., Truong, Triet M., Fields, Shannon, Shafarman, William N., McCandless, Brian E., Baxter, Jason B.. 2021-08-26. Quantifying Bulk and Surface Recombination in CdTe Solar Cells Using Time-Resolved Terahertz Spectroscopy. https://doi.org/10.1109/pvsc43889.2021.9518559

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