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Semiconductor Physics, Quantum Electronics & Optoelectronics. 2006. V. 9, N 3. P. 094-098.
Defects with deep donor and acceptor levels in nanocrystals of CdTe and CdSe
V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 45, prospect Nauky, 03028 Kyiv, Ukraine
Abstract. The defects in CdTe and CdSe nanocrystals were studied by comparing the
photoluminescence spectra and cyclic voltammetry dependences, which enabled us to
identify two main electron levels in CdTe and four in CdSe NCs. In CdTe nanocrystals
these levels are: a hole trap at the energy EV + 0.5 eV and an electron trap at Ec – 0.5 eV.
In CdSe nanocrystals, detected were two hole traps at Ev + 0.52 eV and Ev + 0.8 eV, and
two electron traps at Ec – 0.25 eV and Ec – 0.65 eV. The 2+/1+ level of VCd or Tei is
suggested to be an acceptor, and the 2–/1– level of an antisite defect is suggested to be a
donor level.
Keywords: donor, acceptor, deep levels, nanocrystal.
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