화학공학소재연구정보센터
Journal of the American Ceramic Society, Vol.83, No.5, 1241-1246, 2000
Characterization of photoluminescent (Y1-xEux)(2)O-3 thin films prepared by metallorganic chemical vapor deposition
The purpose of this study was to identify and correlate the microstructural and luminescence properties of europium-doped Y2O3 (Y1-xEux)(2)O-3 thin films deposited by metallorganic chemical vapor deposition (MOCVD), as a function of deposition time and temperature. The influence of deposition parameters on the crystallite size and microstructural morphology were examined, as well as the influence of these parameters on the photoluminescence emission spectra. (Y1-xEux)(2)O-3 thin films were deposited onto (111) silicon and (001) sapphire substrates by MOCVD. The films were grown by reacting yttrium and europium tris(2,2,6,6-tetramethyl-3,5-heptanedionate) precursors with an oxygen atmosphere at low pressures (5 torr (1.7 x 10(3) Pa)) and low substrate temperatures (500 degrees-700 degrees C). The films deposited at 500 degrees C were smooth and composed of nanocrystalline regions of cubic Y2O3, grown in a textured [100] or [110] orientation to the substrate surface. Films deposited at 600 degrees C developed, with increasing deposition time, from a flat, nanocrystalline morphology into a platelike growth morphology with [111] orientation. Monoclinic (Y1-x Eu-x)(2)O-3 was observed in the photoluminescence emission spectra for all deposition temperatures. The increase in photoluminescence emission intensity with increasing postdeposition annealing temperature was attributed to the surface/grain boundary area-reduction effect.