Crystallinity and surface roughness dependent photoluminescence of Y1-xGdxVO4:Eu3+ thin films grown on Si (100) substrate

Gd-substitution dependency on the photoluminescence in YVO4:Eu3+ films grown on Si (100) substrates have been investigated by analyzing the crystalline phase and surface morphology of the films. The substitution of Gd induced not only the change of crystallinity but also the surface roughness of the films. The change of the preferred orientation in the films can be explained on the basis of the lattice mismatch between the film and Si (100) substrate. Also, the surface roughness of the films shows the similar behavior to the grain size as a function of Gd amounts. The photoluminescence (PL) intensity obtained from the Y1-xGdxVO4:Eu3+ films grown under ooptimized conditions have indicated that the PL intensity is more dependent on the surface roughness than the crystallinity of films. In particular, the incorporation of Gd into the YVO4 lattice remarkably enhanced the intensity of PL and the highest emission intensity of Y0.57Gd0.40Eu0.03VO4 film was 3.3 times higher than that of YVO4:Eu3+ film. (c) 2009 Published by Elsevier B.V.