Study on electronic structure and optoelectronic properties of indium oxide by first-principles calculations

The electronic structure of In2O3 has been studied for the first time using a first-principles calculation method based on the density functional theory. Although the complexity of the crystal structure of In2O3 which contained 40 atoms in its unit cell had prevented studies of its electronic structure, we were able to study it using the characteristic of minimum basis sets of the linear muffin-tin orbital method with atomic sphere approximation. The calculated partial density of states (PDOS) showed that the valence bands were composed mainly of oxygen 2p-like states and the conduction bands consisted mainly of indium 5s-like states with free-electron-like character. The results of PDOS analysis were used to analyze the spectra from X-ray photoelectron spectroscopy and bremsstrahlung isochromat spectroscopy. Calculated results were also used to interpret optoelectronic properties of tin-doped indium oxide.