High temperature response of a single crystal CVD diamond detector operated in current mode

In the last years there has been an increasing interest in diamond detectors working in harsh environments characterized by high temperature and intense gamma and neutron fluxes. In this work the operational performances of an artificial single crystal CVD diamond detector operating in current mode at high temperature (HT) are investigated. The detector leakage current was first characterized versus the temperature and the biasing voltage (HV), then the detector was exposed to intense Co-60 gamma-ray fluxes, and its response in terms of normalized current'' (here defined as measured current minus leakage current normalized to gamma dose-rate or gamma flux) as well as its time dependent behavior were studied at temperatures ranging from 300 K (room temperature) up to 625 K. The detector response resulted linear to HV and dose-rate up to about 600 K. At higher temperatures, saturation of the measured net current as well as polarization effects were observed. An attempt to give an heuristic explanation of some of the observed phenomena is addressed too.