Korean Journal of Materials Research ISSN:1225-0562(Print) 2287-7258(Online) 한국재료학회지

Dy³⁺ and Eu³⁺-codoped SrWO₄ phosphor thin films were deposited on sapphire substrates by radio frequency magnetron sputtering by changing the growth and thermal annealing temperatures. The results show that the structural and optical properties of the phosphor thin films depended on the growth and thermal annealing temperatures. All the phosphor thin films, irrespective of the growth or the thermal annealing temperatures, exhibited tetragonal structures with a dominant (112) diffraction peak. The thin films deposited at a growth temperature of 100 °C and a thermal annealing temperature of 650 °C showed average transmittances of 87.5% and 88.4% in the wavelength range of 500-1100 nm and band gap energy values of 4.00 and 4.20 eV, respectively. The excitation spectra of the phosphor thin films showed a broad charge transfer band that peaked at 234 nm, which is in the range of 200-270 nm. The emission spectra under ultraviolet excitation at 234 nm showed an intense emission peak at 572 nm and several weaker bands at 479, 612, 660, and 758 nm. These results suggest that the SrWO₄: Dy³⁺, Eu³⁺ thin films can be used as white light emitting materials suitable for applications in display and solid-state lighting.