Abstract
Low open-circuit voltages (850-870 mV), due to excessive bulk and surface recombination, currently limit CdTe photovoltaic efficiencies. Here, we study surface recombination in single crystals with single-photon excitation time-resolved photoluminescence (1PE-TRPL) to measure minority carrier lifetimes. Typically, minority carrier lifetimes of untreated undoped CdTe material as measured by 1PE-TRPL are ∼100 ps or less, even though their bulk lifetimes as measured by two-photon excitation TRPL can reach 100 ns. Such short 1PE-TRPL lifetimes indicate very high surface recombination velocities exceeding 100 000 cm/s. Here, we examine treatments that can reduce surface recombination and discuss different ways of evaluating their efficacy.
Original language | American English |
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Article number | 6945796 |
Pages (from-to) | 382-385 |
Number of pages | 4 |
Journal | IEEE Journal of Photovoltaics |
Volume | 5 |
Issue number | 1 |
DOIs | |
State | Published - 2015 |
Bibliographical note
Publisher Copyright:© 2011-2012 IEEE.
NREL Publication Number
- NREL/JA-5K00-62433
Keywords
- Cadmium compounds
- charge carrier lifetime
- photoluminescence
- photovoltaic cells