Abstract
Using experiments and theory, we analyze 'carrier-lifetime-killer' semiconductor bulk defects in CdTe. We can estimate the concentration of tellurium antisite (TeCd) recombination centers in undoped CdTe from the kinetic modeling of injection-dependent photoluminescence (PL) lifetimes. For the Cd-rich stoichiometry, the concentration of lifetime-limiting [TeCd] is ≥1013 cm-3. For the Te-rich stoichiometry, we find a smaller hole-capture rate constant than predicted by theory, which could be because of TeCd association with the Te interstitials. We also compare PL emission spectra, carrier lifetimes, and radiative efficiencies for Cu, P, and As doping and analyze the microscopic distribution of carrier lifetimes in As-doped single-crystal CdTe. In all the cases examined here, point defects are the dominant bulk recombination centers. Carrier lifetimes are the longest in undoped CdTe, but radiative efficiencies are the highest with group-V doping.
Original language | American English |
---|---|
Article number | 8456586 |
Pages (from-to) | 1754-1760 |
Number of pages | 7 |
Journal | IEEE Journal of Photovoltaics |
Volume | 8 |
Issue number | 6 |
DOIs | |
State | Published - Nov 2018 |
Bibliographical note
Publisher Copyright:© 2018 IEEE.
NREL Publication Number
- NREL/JA-5900-71484
Keywords
- Characterization of defects in PV
- charge-carrier lifetime
- CIGS and CdTe thin-film solar cells