Radiation-hard wide bandgap semiconductor radiation detectors can offer advantages over Si detectors in photon counting X-ray spectrometers that need to operate in harsh radiation environments or environments of high temperature (> 20 °C). The cooling apparatus that is normally required to limit the thermally stimulated leakage currents of narrower bandgap detectors, and the shielding which can be necessary to protect detectors from intense radiation, can be reduced or discarded when high temperature tolerant and radiation-hard detectors are used. Some harsh environments where wide bandgap semiconductor radiation detectors could be beneficial are space, gas turbine engines, nuclear power plants, and in the vicinity of deep-sea hydrothermal vents.
Diamond is one such wide bandgap material (Eg = 5.47 eV). Other properties of diamond include chemical inertness and intrinsic resistance to radiation damage. These properties suggest that a diamond detector could be useful in an uncooled X-ray, γ-ray, or electron (β- particle) spectrometer.
This presentation will review recently achieved spectroscopic X-ray, γ-ray, and β- particle detections with a diamond detector at elevated temperatures (≥ 20 °C). The experimentally measured responses of the diamond have also been used to develop a custom Monte-Carlo (MC) model to simulate the detector’s response to illuminations of β particles, X-rays, and γ-rays emitted from natural Gd foils after thermal neutrons are absorbed. Diamond’s quantum detection efficiency (QE) for hard X rays and γ rays is relatively low in comparison to the QE for electrons, thus making it possible to collect electron spectra from the Gd layer neutron conversion products which are not overwhelmed by contributions from the γ-rays and X-rays emitted by the Gd.
