STRUCTURAL AND PHOTOLUMINESCENT CHARACTERISTICS OF YTTRIUM-ALUMINUM OXIDE-FILMS DOPED WITH TB, EU OR CE

The structural and room temperature luminescent characteristics of rar e earth doped yttrium-aluminum oxide films deposited by the spray pyro lysis technique at low temperatures have been studied as a function of the deposition parameters such as substrate temperature and dopant co ncentration. The spraying solution is prepared by mixing yttrium and a luminum chlorides in water, and the incorporation of the rare earth do pants is achieved by adding chloride salts of these elements to this s olution. The photoluminescent emission from Tb- and Eu-doped films hav e the spectral characteristics typical of radiative transitions among the electronic energy levels associated with the 3+ ionized states of these atoms. The Ce doped films, on the other hand, present a blue emi ssion that is associated with transitions within the energy states of the CeCl3; molecule used for the doping process of the film. The X-ray diffraction measurements of these films indicated poor crystallinity in general, with small crystalline peaks and a broad amorphous compone nt that tend to be reduced as the deposition temperature is increased. (C) 1998 Elsevier Science S.A. All rights reserved.