Efficiency of depleted UO2 based semiconductor neutron detectors-A Monte Carlo simulation study

In the present work, Monte Carlo simulations using GEANT4 were performed to estimate the efficiency of depleted UO2 based direct and indirect conversion semiconductor neutron detectors. Efficiency was found to increase linearly with increasing thickness of UO2 and was found to be 0.024% at a thickness of 100 µm in direct conversion configuration. But in the case of indirect conversion, detector efficiency was found to be ∼ 0.00045% at a thickness of 20 µm and thereafter it showed a saturation. Even though the efficiencies of UO2 are much lower than the conventional counterpart detectors based on 10B, the fission products generated in UO2 were found to have much higher energies, which in turn yield better gamma discrimination.