| AVS 54th International Symposium | |
| Thin Film | Tuesday Sessions |
| Session TF-TuP |
| Session: | Aspects of Thin Films Poster Session |
| Presenter: | H. Fukada, Kanazawa Institute of Technology, Japan |
| Authors: | H. Fukada, Kanazawa Institute of Technology, Japan S. Matsui, Kanazawa Institute of Technology, Japan T. Miyata, Kanazawa Institute of Technology, Japan T. Minami, Kanazawa Institute of Technology, Japan |
| Correspondent: | Click to Email |
In this paper, we describe the photoluminescent (PL) and electroluminescent (EL) characteristics from Eu-activated CaAl2O4-based multicomponent oxide thin-film phosphors. Various Eu-activated CaAl2O4-based thin-film phosphors were developed using multicomponent oxides composed of CaAl2O4 with CaGa2O4 or CaIn2O4 as the host material. The phosphor thin films were prepared on thick BaTiO3 ceramic sheets by either a conventional or a combinatorial r.f. magnetron sputtering deposition (rf-MSD) using a powder target. In ((CaAl2O4)1-X-(CaGa2O4)X):Eu phosphor thin film preparation, a powder mixture of CaO, Al2O3 and Eu2O3 and/or CaO, Ga2O3 and Eu2O3 calcined at a temperature range of 1000-1300oC in either a pure Ar gas or air was used as the target. The sputter depositions were carried out under the following conditions: atmosphere, either a pure Ar or an Ar+O2 (2%), pressure, 6 Pa; r.f. power, 140 W; and substrate temperature, 100-350oC. Some deposited thin films were postannealed in either air or an Ar+H2 (5%) gas atmosphere for 30-300 minutes at 500-1000oC. It was found that PL characteristics of CaAl2O4:Eu phosphor thin films were significantly affected by the deposition and postannealing conditions. Intense yellow-green (Y-GL) PL emission was observed from as-deposited CaAl2O4:Eu thin films prepared in a pure Ar sputter gas atmosphere using a powder target calcined at 1000oC in air. In addition, blue (B) PL emission was observed in CaAl2O4:Eu thin films postannealed in an Ar+H2(5%) gas atmosphere at a temperature above approximately 800oC, and the intensity of the B emission increased as postannealing temperature was increased. The EL device fabricated using a postannealed CaAl2O4:Eu thin film as the emitting layer exhibited red EL emission. In addition, in the ((CaAl2O4)1-X-(CaGa2O4)X):Eu multicomponent oxide phosphor thin films were prepared by the combinatorial rf-MSD method. The obtained PL and EL characteristics from these multi-component oxide phosphor thin films were considerably affected by the postannealing conditions as well as the chemical composition (CaGa2O4 content or Ga/(Al+Ga) atomic ratio; X