Stability of indium-tin-oxide and its optical properties: A first-principles study

Various doping sites of Sn in the In2O3 system have been modeled and simulated by the first-principles. The energy favorable site of Sn in In2O3 is found to be on the b-site, which is consistent with experiments. The doping of Sn into interstitial sites is experimentally possible due to the fluctuation in energy, and the intrinsic oxygen vacancies in In2O3 favor the formation of Sni. As Sni in doped ITO can drastically change the transparency in the visible light range, it is necessary to control the preparatory conditions to avoid Sn doping in interstitial sites for realizing ideal transparency in visible light range. By using the LDA+U approach, the band structures of In2−xSnxO3 (x≤0.125) are calculated, which are in substantially better agreement with the experimental values than previous first-principles results.