Direct Fast-Neutron Detection with Diamond Homoepitaxial Me–p––p+ Structures

The results of studies on fast-neutron detectors application of homoepitaxial Me–p––p+ structures are reported. Epitaxial boron doped (NA = (4–8) × 1014 cm–3) layers 65 μm thick were grown on highly boron doped HPHT diamond plates by CVD. The Schottky contact on epitaxial layer with 17 mm2 area was fabricated by 30 nm Pt deposition. The Ti(30 nm)/Pt(30 nm)/Au(50 nm) metallization scheme was used as an ohmic contact on the backside of the p+ HPHT diamond plate. The fast-neutron detection efficiency measured on 241Am–Be source at operational bias of 75 V (the depletion region is 10.6 µm) amounted to 6 × 10–5 puls./neutron.