Characterization of CdTe diode detector with depletion layer modulation for energy discrimination X-ray imaging

A new method of pseudo-energy discrimination X-ray imaging with conventional integration-type CdTe flat panel detectors is proposed. The energy selectivity of the detector can be controlled by modulating the thickness of the depletion layer with bias voltage. The analysis, considering the charge collection efficiency in the conventional commercial CdTe-based Schottky diode detector, was done to characterize the energy discrimination capability obtained by the developed method. The result has implied that the two energy bands as 30-60 keV and over 80 keV can be discriminated using two bias voltages. The Monte-Carlo simulation and the energy spectrum measurements with single pixel In/CdTe/Pt Schottky diode detectors were carried out to verify the pseudo-energy discrimination capability.