Structural and optical properties of indium oxide thin films synthesized at different deposition parameters by spray pyrolysis

Indium oxide polycrystalline films have been synthesized by the spray pyrolysis method. The deposition has been carried out on cleaned glass substrates. The aqueous solution of indium chloride was used as a precursor solution. Thin films were deposited with two different molar concentrations of 0.02 and 0.03, at three different temperatures ranging from 300 to 400 degrees C with an increment of 50 degrees C. Structural and optical properties were studied using XRD and UV-Vis spectroscopy. The polycrystallinity of the film can be assured from the XRD data. Absorption and transmission spectra were examined in the 300-1000 nm spectral range. For the investigated films, the transmission coefficient reaches a maximum of 80% for the 0.02 M sample at 400 degrees C. Indium oxide is a material showing both direct and indirect bandgap. The direct bandgap values range between 3.53 eV and 3.87 eV. Optical parameters like refractive index and extinction coefficient were also calculated for deposited films at various temperatures. The investigation was done to optimize the deposition parameters for gamma sensing applications. Copyright (C) 2022 Elsevier Ltd. All rights reserved.