Defect mechanisms in the In2O3(ZnO)k system (k=3, 5, 7, 9)

The defect chemistry of several compounds in the In2O3(ZnO)(k) series (k = 3, 5, 7, and 9) was investigated in bulk specimens by analysis of the dependence of their conductivity on the oxygen partial pressure. The resulting Brouwer slopes were inconsistent with a doubly charged oxygen vacancy defect model, and varied with the phase. The k = 3 phase had behavior similar to donor-doped In2O3, and the behavior of the other phases resembled that of donor-doped ZnO. The donor in both cases is proposed to be In occupying Zn sites. First principles calculations of the formation energy of intrinsic defects in this system support the proposed models. The present work expands prior theoretical analysis to include acceptor defects, such as cation vacancies (V-Zn, V-In) and oxygen interstitials (O-i). (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4764924]