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

Journal Article · 25 August 2021 · Conference Record of the IEEE Photovoltaic Specialists Conference

DOI: https://doi.org/10.1109/pvsc43889.2021.9518559 · OSTI ID:1888614

Taheri, Mohammad M. ^[1]; Truong, Triet M. ^[2]; Fields, Shannon ^[3]; Shafarman, William N. ^[3]; McCandless, Brian E. ^[3]; Baxter, Jason B. ^[2]

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1. Drexel Univ., Philadelphia, PA (United States); Drexel University
2. Drexel Univ., Philadelphia, PA (United States)
3. Univ. of Delaware, Newark, DE (United States)

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, ~6x10⁴ cm/s, and indicated that CdTe/CdS interface recombination velocity had no significant impact on carrier dynamics.

• Research Organization: Drexel Univ., Philadelphia, PA (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• Grant/Contract Number: EE0008986
• OSTI ID: 1888614
• Journal Information: Conference Record of the IEEE Photovoltaic Specialists Conference, Journal Name: Conference Record of the IEEE Photovoltaic Specialists Conference Vol. 2021; ISSN 0160-8371
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English