PHOTOSTIMULABLE LUMINESCENCE AND IMAGING IN VAPOR-DEPOSITED BAFCL-EU THIN-FILM PHOSPHORS

Thin films of BaFCl:Eu with photostimulable luminescence (PSL) were gr own by vapor deposition. For substrate temperatures at or below 350 de grees C, films were optically transparent and exhibited higher resolut ion in x-ray imaging than a commercial, particulate PSL phosphor scree n, when luminescence was stimulated by scanning with a focused HeNe la ser. Although post annealing films in a hydrogen atmosphere at 600-900 degrees C increased their PSL signal, which was relatively weak in as -deposited films, annealing reduced imaging resolution, apparently bec ause of an increase in optical scattering of the focused laser. The im plications of hydrogen annealing for the PSL mechanism are also discus sed. (C) 1998 American Institute of Physics.