Microstructural, morphological and optical properties of sprayed thin films of indium doped gadolinium oxide (Gd2O3: In)

Abstract

This paper featured a study on undoped and Indium doped Gadolinium oxide Gd₂O₃: In thin films, elaborated on a glass substrates at temperature of 500 °C by homemade Spray Pyrolysis technique, at different Indium concentrations as follow 0, 2, 4, 6 and 8 at %. This thin layers, where a subjects to a numerous characterization techniques to study the effect caused by introducing the dopant element “Indium” in Gadolinium oxide lattice on the structural properties (X-Ray Diffraction and Raman spectroscopy) and optical properties. The structural characterization carried by the X-ray diffraction (XRD) reveals a polycrystalline Monoclinic B-type structure for all Gd₂O₃:In thin films. Moreover, these findings are verified by the Raman spectroscopy results. Concerning the optical properties of our thin films, the optical measurements carried by UV-VIS-NIR spectrophotometer shows an increase in the transmittance value within the visible region [370-900 nm] and in the band gap energy value by raising Indium doping rate from 0 at % to 6 at %, also the disorder caused inside the thin films were estimated by the Urbach equation. That said, the 2 at % Indium doped gadolinium oxide thin film provides interesting results that can be applied in solar cells as an optical window material.