Possible n–type carrier sources in In2O3(ZnO)k

Abstract

Homologous compounds with the formula In2O3(ZnO)k, where k is an integer, have potential applications as transparent conducting oxides and high temperature thermoelectric materials. In this study, we focus on the defect properties. Using the k = 3 phase as a prototype, we calculate with the first-principles method the defect formation energies and transition levels of the most probable n-type carrier producers, which include oxygen vacancy (VO), indium antisite on zinc (InZn), indium interstitial (Ini), and zinc interstitial (Zni). The site-preference of these defects has been explored by comparing the total energies of defects at different sites. Under the n-type environment, InZn has a low formation energy and meanwhile a transition energy level close to the conduction band minimum (CBM); VO also has a lower formation energy, however a deep transition energy level in the band gap; the cation interstitials have high formation energies, although their defect transition energy levels are quite shallow. Bes...