(Sr{sub}(1-x)Ca{sub}x)S:Cu,F solid solution powder phosphors were prepared, then the dependence of photoluminescent (PL) properties of the phosphors on Sr/Ca compositional ratio were discussed. Peak wavelength ranged between 420nm for CaS:Cu,F and 474nm for SrS:Cu,F at PL measurements. Powder phosphors were then used for the preparation of thin films by the electron beam evaporation. The photoluminescence peak of the thin films ranged from 430nm to 477 nm. The luminescence characteristics as well as the solid solution composition of prepared thin films depended on the annealing time. Furthermore, the composition of the solid solution of thin films and pellet were different. The PL intensity of the thin films was increased by annealing for 10 minutes or more at 900℃. However, the Pt peak was shifted to longer-wavelengths, and the concentration of impurities increased. We succeeded to obtain thin films without impurities, by reducing annealing time to less than 7 minutes. Optimized solid solution thin films were used in TFEL structures and characteristics of fabricated devices are discussed.
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