Properties of gallium oxide thin film prepared on silicon substrate by spray pyrolysis method

Gallium oxide has attracted attention as an alternative to other costly materials in their applications as solar-blind photodetectors. It has been synthesized by several physical methods. In this work, gallium oxide thin films have been synthesized by using cost-effective spray pyrolysis method on silicon substrates at an appropriate temperature. Fourier transform infrared (FTIR) has been used to examine the chemical bonding, and the spectra revealed bands that can be assigned to vibrations corresponding to Ga–O and Ga–O–Ga bonds, 419.29 and 622.88 cm−1, respectively, for β-phase of Ga2O3. Scanning electron microscopy (SEM) images obtained in the study of the surface morphology revealed nanoflakes and pores, spread over the film at 850 °C, which reduced drastically as the temperature was raised to 900 °C, improving the thin film homogeneity. Optical studies carried out with spectrophotometer showed high absorbance in the Ultraviolet (UV) region with main peaks at 228.3 and 283.9 nm. The optical band gap of 4.9 eV was obtained for films annealed at 900 °C confirming the formation of β-phase gallium oxide film.