| Summary: | Radio frequency (RF)-sputtered white-light-emitting BaWO _4 :Dy ^3+ thin films were deposited at four different temperatures for application in electroluminescence devices and displays. All thin films crystallized to achieve a tetragonal structure with a dominant BaWO _4 (112) diffraction peak, irrespective of growth temperature. Two types of trapezoid grains with average sizes of approximately 250 and 530 nm evolved at a deposition temperature of 100 °C. Upon 234 nm excitation, the two main emission spectra of the BaWO _4 :Dy ^3+ thin films exhibited a 572 nm yellow band arising from the ^4 F _9/2 → ^6 H _13/2 transition and a 477 nm blue line resulting from the ^4 F _9/2 → ^6 H _15/2 transition of Dy ^3+ . As the growth temperature increased, the emission intensities of all bands increased slowly, approached a maximum at 300 °C, and then decreased markedly at 400 °C, with a chromaticity coordinates of (0.314, 0.361), a band gap of 4.56 eV, and a transmittance of 98%. These results indicate that the white-light emission of RF-sputtered BaWO _4 :Dy ^3+ thin films can be fully realized by varying the growth temperature.
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