Phase transitions from semiconductive amorphous to conductive polycrystalline in indium silicon oxide thin films

The enhancement in electrical conductivity and optical transparency induced by aphase transition fromamorphous topolycrystalline in lightly silicon-doped indium oxide (InSiO)thin films is studied. Thephase transition caused by simple thermal annealing transforms the InSiOthin films fromsemiconductors to conductors.Silicon atoms form SiO4 tetrahedra in InSiO, which enhances the overlap of In 5s orbitals as a result of the distortion of InO6 octahedral networks. Desorption of weakly bonded oxygen releases electrons from deep subgap states and enhances the electrical conductivity and optical transparency of thefilms. Optical absorption andX-ray photoelectron spectroscopy measurements reveal that thephase transition causes a Fermi energy shift of ∼0.2 eV.

Source: Applied Physics Letters - November 29, 2016 Category: Physics Authors: Nobuhiko Mitoma, Bo Da, Hideki Yoshikawa, Toshihide Nabatame, Makoto Takahashi, Kazuhiro Ito, Takio Kizu, Akihiko Fujiwara and Kazuhito Tsukagoshi Source Type: research