CHARACTERISTICS OF SRSCECL3 TFEL DEVICE PREPARED BY MULTISOURCE DEPOSITION METHOD WITH H2S AND SR METAL

A new preparation method is proposed for the SrS:CeCl3 phosphor layer for the use in blue-emitting electroluminescent devices by advanced multi-source deposition method using Sr metal, H2S, and CeCl3. This technique eliminates the problems due to sulfur coevaporation, i.e., serious damages to pumping system, difficulty of pressure control during deposition, and disconnection of leading wires. The stoichiometry of the film was determined using Rutherford backscattering spectroscopy (RBS). The volume density of the film which was calculated by RBS and optical ellipsometer measurements was confirmed to have a value close to that of bulk. H2S pressure during the deposition affected the crystallinity of the film and the characteristics of luminance-voltage (L-V) curves of the device.