Radiation detection with polycrystalline CVD diamond films: effects of film thickness and irradiation on detector performance

Abstract In this work, radiation detectors based on a polycrystalline diamond film were studied. Polycrystalline chemical vapor-deposited diamond films with varied thickness up to 55 μm were prepared on silicon substrates. Circular Ti/Au electrical contact pads with diameters between 1 and 3 mm were processed on the diamond films. The detector structures were tested with 5.5 MeV alpha particles generated by 241 Am radioisotope. They were irradiated with 4 MeV protons to a maximum fluence of 10 16 p/cm 2 . The irradiated samples were analysed using scanning electron microscopy, Raman spectroscopy, and positron annihilation lifetime spectroscopy. Additionally, the polycrystalline diamond detectors were used to detect fast neutrons with an energy of 15.5 MeV, which demonstrated their potential for use in neutron monitoring.