Growth Mechanism and Structural Elucidation of Indium Oxide Microstructures Prepared by Carbothermal and Hydrogen Reduction Processes

In this study, the growth mechanism for the deposition of pure In2O3 crystal and indium-In2 O3 mixed-phase films is proposed for the carbothermal and hydrogen reduction growth processes, respectively. X-ray diffractograms confirm the formation of the pure In2O3crystal and indium-In2O3 mixed-phase films. Surface morphology observation show pure microaggregates for the pure In2O3 film, and a combination of microclusters and microspheres for the mixed-phase film. The initially condensed seed-layer in the form of small solid-crystals and liquid-catalyst, serving as nucleation sites are suggested to result to the development of the pure and indium-In2O3 mixed-phase films for the carbo-thermal and hydrogen reduction growth processes, respectively. Composition analyses reveal rich- and deficient oxygen contents for the pure and mixed phase films, respectively thus, supporting the X-ray diffraction results. Optical bandgaps values are found to be 3.07 and 3.85 eV for the pure In2O3 and mixed phase films, respectively. The carbothermal reduction technique has been found to be more appropriate for the growth of pure In2O3 crystal.