Photoluminescence characteristics of ZnGa2O4 thin films prepared by chemical solution method

Abstract

Zinc gallate (ZnGa2O4) thin film phosphors have been formed on ITO glass substrates by a chemical solution method with starting materials of zinc acetate dihydrate, gallium nitrate hydrate and 2-methoxiethanol as a solution. The thin films were firstly dried at 100 °C and fired at 500 °C for 30 min and then, annealed at 500 °C and 600 °C for 30 min under an annealing atmosphere of 3% H2/Ar. XRD patterns of the thin film phosphors showed (311) and (220) peak indicating ZnGa2O4 crystalline phase in which all the (311) peaks of the film phosphors synthesized on ITO glass and soda-lime glass revealed high intensity with increasing annealing temperature from 500 °C to 600 °C. The ZnGa2O4 thin film phosphors represented marked change in AFM surface morphologies according to an annealing temperature under an annealing atmosphere (3% H2/Ar). The film phosphor, annealed at 600 °C, showed the embossed pattern with relatively regular spacing in AFM surface morphology. The ZnGa2O4 thin film phosphors formed on ITO glass, which were annealed at different temperatures and showed distinctive spectra with peak wavelengths of 434 nm and 436 nm in the blue emission region.