| abstract |
An X-ray detector is provided, which can improve detection sensitivity of a photoconductive layer. n Heavy metal halide and halogen are made to be contained in the photoconductive layer. Changes of dark-current characteristics, sensitivity characteristics, and afterimage characteristics by X-ray irradiation are suppressed, thereby the stable photoconductive layer can be made. If surplus halogen is contained in the photoconductive layer, dissociation of halogen in the heavy metal halide crystal structure which is apt to be formed in X-ray irradiation, and generation of crystal defect accompanied with the dissociation of this halogen are suppressed. The dissociation of halogen forms defect level in the photoconductive layer, and yields deep trap of charge, and influences on the dark-current characteristics, the sensitivity characteristics, and the afterimage characteristics. If the surplus of halogen in the photoconductive layer is too much, halogen is deposited at grain boundary, conductivity between fine crystals of photoconductive layer is obstructed, sensitivity characteristics and afterimage characteristics of X-ray conductive layer are obstructed greatly, and afterimage becomes lengthened. |