Photoluminescence intensity enhancement of ion-doped CdWO_4 thin films prepared with pulsed laser deposition

摘要

Samarium-, nickel- and cesium-ion doped CdWO_4 thin films as well as non-doped CdWO_4 thin films were prepared by the pulsed laser deposition (PLD) method. The film thickness and the substrate temperature during PLD were changed to study the role of doped ions on the CdWO_4 lattice. The crystalline CdWO_4 thin films were obtained by PLD on glass substrates at 1073 K. The CdWO_4 (002) XRD signal was more intense on the non-doped, Sm- and Ni-doped PLD films. When the substrate temperature was increased to 1273 K, the peak decreased in intensity, and the (111) peak became more intense than the intensity of the (002) on the ion-doped PLD films whereas the (020) signal was still significant on the non-doped thin film. Photoluminescence spectra were deconvoluted into three components at 2.82, 2.54 and 2.27 eV. The contribution of the yellow PL component at 2.27 eV was relatively high on the doped PLD films prepared at 1073 K. However, the overall PL spectra features on PLD films prepared at 1273 K were almost the same as the (010) single crystal surface. Photoluminescence intensities on the PLD films prepared at 1273 K were significantly intense and exceeded that on the CdWO_4 (010) single crystal surface.