Diamond Detectors

Diamond detectors are most suitable for high energy radiation detection in the harsh environment with improved accuracy. Due to inert nature of the diamond material, the technology needs proper optimisation for metal film adhesion and further bonding and packaging. Synthetic diamond material technology is commercially available around Chemical Vapour Deposition (CVD) to get the poly crystal (pc-diamond) and single crystal (sc-Diamond) substrates in sizes much smaller than conventional semiconductor wafers. CVD Diamond material is preferred over natural diamond owing to higher purity and low leakage currents. Diamond technology development has been aimed with validation by delivering working prototypes of diamond detectors for real-time alpha and neutron detection. The Diamond material is to be made available by the sponsoring agency while fabrication technology development has to be done at CEERI laboratories. The R&D has to be carried out in collaboration with user agency by delivering a number of prototypes during the development stage and finally few number of field compatible detectors will be supplied. The whole activity has been monitored with time target deliverables. More than twenty packaged detectors have been delivered to user agency with required response to high

Fig. 1: Fabricated diamond detectors

Fig. 1: (b) DC characteristics

energy particles. Fabricated detectors with their DC characteristics are shown in Fig. 1 (a&b). Salient features of the technology developed at CSIR-CEERI are:

  • Conversion of H-termination to O-termination of sc-Diamond surfaces
  • Cr/Au metallisation on polished diamond surfaces with stability up to 400 °C
  • Bonding and packaging of Diamond Chip
  • DC characterisation at pA Current levels