In situ growth of blue-emitting thin films of cerium-doped barium chloride hydrate at low temperatures

Blue emission was observed from thin films of barium chloride hydrate doped with cerium. The films were deposited by spray pyrolysis of aqueous solutions with substrate temperatures between 250 and 450 degreesC. The cathodoluminescence (CL) spectrum consists of two peaks at 443 and 485 nm due to 4f-5d transitions of cerium ion. The dependence of the emission band on deposition temperature and Ce/Ba ratio is discussed. The CL luminance and luminous efficiency at 5 kV were 120 cd/m(2) and 0.48 lm/W, respectively, for the films deposited at temperatures as low as 250 degreesC. The results indicate barium chloride hydrate doped with cerium is a blue phosphor that exhibits relatively efficient luminescence after processing at low temperatures. (C) 2003 American Institute of Physics.