Abstract
The effects of the annealing temperature on the structural, morphological, and luminescent properties of SrWO4:Sm3+ thin films grown on quartz substrates by radio-frequency magnetron sputtering were investigated. The thin films were annealed at various annealing temperatures for 20 min in a rapid thermal annealer after growing the thin films. The experimental results showed that the annealing temperature has a significant effect on the properties of the SrWO4:Sm3+ thin films. The crystal structure of the as-grown SrWO4:Sm3+ thin films was transformed from amorphous to crystalline after annealing at 800℃. The preferred orientation along (112) plane and a significant increase in average grain size by 820 nm were observed with increasing the annealing temperature. The average optical transmittance in the wavelength range of 500~1,100 nm was decreased from 72.0% at 800℃ to 44.2% at an annealing temperature of 1,000℃, where the highest value in the photoluminescence intensity was obtained. In addition to the red-shift of absorption edge, a higher annealing temperature caused the optical band gap energy of the SrWO4:Sm3+ thin films to fall rapidly. These results suggest that the structural, morphological, and luminescent properties of SrWO4:Sm3+ thin films can be controlled by varying annealing temperature.