The Influence of Annealing Temperature on Structure, Morphology and Optical Properties of (InxGa1-x)2O3 Films

In our work, (InxGa1-x)(2)O-3 films were obtained on sapphire (0001) substrates by radio frequencymagnetron sputtering. The influence of annealing temperature on crystalline structure, morphology, transmittance, and the optical band gap was investigated in detail. X-ray diffraction analysis showed that the as-prepared (InxGa1-x)(2)O-3 film was amorphous and the crystal quality was improved with the increasing of annealing temperature. The ((4) over bar 02) peak shifted to larger angle with the increasing of annealing temperature. Energy Dispersive Spectrometer analysis showed decreasing trend of In content. X-ray diffraction analysis and Energy Dispersive Spectrometer jointly indicated the peak shift due to the decreasing of In content and variation of tensile stress. The morphology feature of films was investigated by atomic force microscope. The island structure existed in the surface of films at the annealing temperature from 500 degrees C to 900 degrees C and when annealing temperature is 1000 degrees C, islands disappeared and needle-like structure occurred. Transmittance spectra revealed excellence optical properties of films and absorption coefficient spectra showed the decreasing of band gaps of films with the increasing of annealing temperature. It could be attributed to the decreasing of In content and variation of tensile stress. (c) The Author(s) 2019. Published by ECS.