Response function measurement of a synthetic diamond radiation detector for 14 MeV neutrons

The response function of a diamond radiation detector using a synthetic type IIa single diamond crystal for 14 MeV neutrons was measured. There was severe trapping of electrons in the synthetic diamond crystals used in this study. Accordingly, a prototype diamond radiation detector using the synthetic type IIa single diamond whose thickness was 0.1 mm was used with high bias voltage up to 1000 V, i.e., electric field of 100 kV/cm. The measurement resulted in the first observation of a 14 MeV neutron peak corresponding to C-12(n, alpha)Be-9 reactions by a synthetic diamond radiation detector. Energy resolution of the prototype detector for 14 MeV neutrons was 9%. Experimental detection efficiency of the detector was consistent with calculated detection efficiency. Synthetic diamond crystals which do not have trapping of charge carriers are indispensable in order to improve energy resolution for 14 MeV neutrons. (C) 1999 American Institute of Physics. [S0034-6748(99)53301-7].