Silicon carbide neutron detectors for reactor monitoring in subcritical conditions

Silicon carbide (SiC) semiconductor detectors offer key advantages for radiation detection, including a wide bandgap, high thermal conductivity and radiation hardness, making them ideal for applications in harsh environments. Engineering and optimization of dedicated neutron converter components can enable achieving high detection sensitivities, comparable to BF 3 or 3 He detectors of the same physical dimensions. This study explores the use of wide-area SiC Schottky Barrier Diodes (SBDs) for neutron flux measurements in a nuclear reactor in subcritical conditions. Two detectors, fabricated at the National Institutes for Quantum Science and Technology in Japan and equipped with 6 LiF converter layers, were tested at the Jožef Stefan Institute TRIGA reactor in Slovenia using the Libera MONACO 3 system, developed at the French Atomic and Alternative Energies Commission and manufactured by the Instrumentation Technologies company in Slovenia. Results showed excellent performance, in comparison to a Centronic FC165 fission chamber, routinely used for this purpose. SiC detectors and standalone neutron converter components also have a high educational value, allowing for visual and hands-on demonstrations of neutron detection aspects and phenomena. Such activities are implemented in the framework of the European Nuclear Experimental Educational Platform (ENEEP).