Defect Structure of Cu-Doped Cadmium Selenide

Abstract

High‐temperature conductivity and copper solubility in CdSe is measured over the range 600 to 900°C as a function of temperature and cadmium and selenium vapour pressure. It is found that in cadmium vapour (pCd > 10−1 atm) below 750°C the main part of copper is in electrically inactive form and with increasing temperature transfers to the electrically active interstitial form Cu i˙ The activation energy of transference is found to be (2.0 ± 0.28) eV. In cadmium vapour the incorporation of copper occurs by the mechanism of controlled electronic imperfections with the electroneutrality condition (ENC) n = Cui and in selenium vapour by the mechanism of controlled atomic imperfections with ENC Cu i˙ = (Cu i˙VCd)′.

Effect of copper and chlorine on the properties of SiO2 encapsulated polycrystalline CdSe films

“…12,13,18,25,26 Opik et al 12 performed resistivity measurements on CdSe crystals doped with 7 × 10 18 atoms cm -3 of copper by the surface method and reported a carrier activation energy of 1.02 eV which is similar to the value of 1.1 eV observed in this work. 12,13,18,25,26 Opik et al 12 performed resistivity measurements on CdSe crystals doped with 7 × 10 18 atoms cm -3 of copper by the surface method and reported a carrier activation energy of 1.02 eV which is similar to the value of 1.1 eV observed in this work.…”

“…Robinson et al 13 reported that this level was a defect involving native acceptors and identified this as the main sensitizing center in their copper doped films but found no evidence of any association of this level with the copper level they also observed. Conversely, Ermolovich et al 4 reported an increase in the magnitude of the luminescence peak associated with this level in their copper doped films relative to their undoped films while, Opik et al 12 postulated that the copper acts as an acceptor in the CdSe by forming a complex with this level.…”

“…Many authors [12][13][14] have reported the level at about 1.05 ± 0.05 eV below the conduction band and different properties and interactions with copper have been reported for it. Robinson et al 13 reported that this level was a defect involving native acceptors and identified this as the main sensitizing center in their copper doped films but found no evidence of any association of this level with the copper level they also observed.…”

“…Opik et al 12 postulated that the copper acts as an acceptor in CdSe by forming a complex with the V Cd -defect, i.e. Opik et al 12 postulated that the copper acts as an acceptor in CdSe by forming a complex with the V Cd -defect, i.e.…”

Co-operativity in a nanocrystalline solid-state transition

“…S2 and Supplementary Table S1). Cu þ is a common interstitial dopant in CdSe 19,20 . It is known that such dopants do not necessarily disrupt the excitonic band or the ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms3933 overall crystallographic structure of CdSe 18,19 , which is consistent with our optical and electron diffraction measurements.…”