Fast, High Flux, Photovoltaic Cdte Detector

A recently invented CdTe radiation detector designed for high flux applications has been improved to give excellent response over a wide range of x-ray and gamma-ray fluxes. This device operates without an externally applied bias and has no dark current, which makes it very sensitive even at low flux. Measurements over a range of 10-1R/hr to 106 R/hr (Flux of ~ 104 to 1011 photons/cm2-sec) show both nearly linear response and high signal-to-noise. Afterglow has been reduced dramatically so that 1 ms time response can be achieved. This advance opens the possibility of using this semiconductor in the "current mode" of operation for both medical and industrial applications.