Evaluation of ZnS-family phosphors for neutron detectors using photon counting method

A neutron detection sheet composed of ZnS:Ag as phosphor and 6LiF as neutron converter has been conventionally used for neutron detectors including imaging detectors because of its larger luminescence rate for α ray and shorter lifetime. However, the week point of ZnS:Ag phosphor is the slow component of the lifetime. Thus, we began to investigate other ZnS-family phosphors without the slow component of lifetime for neutron detectors using the photon counting method which needs a smaller number of photons of one order of magnitude. In this study, ZnO:Zn, ZnO:Ga, ZnSSe:Ag phosphor ceramics without the slow component of lifetime has been tried to fabricate using an electric furnace or a Spark Plasma Sintering (SPS) apparatus to appropriate for neutron detectors under high counting rates. The ZnO:Zn fabricated by means of the SPS method had the fastest lifetime of 4 ns though its detection efficiency was to be one-eighths as compared with a standard ZnS:Ag/6LiF detection sheet