The response of an Al-10B4C coupled neutron detector based on PIPS technology to Cf-252

Abstract

After decades of discussions, it has been firmly established that detectors made of silicon-based semiconductor materials can be effectively used for neutron detection by simply coating them with suitable substances. The incident thermal neutrons interact with the coating neutron-sensitive materials such as 10B and 6LiF, resulting in the production of secondary charged particles which can be effectively detected in the sequencial silicon substrate. In this article, the detector system was designed with a coupled neutron detector structure which combined a silicon detector with a 10B4C film in various forms. The 10B4C layer was deposited on the substract with electron beam evaporation method. Two kinds of structrue were discussed: (1) one was the direct contact neutron detector by depositing 10B4C directly onto the front surface of silicon-based detectors; (2) the other was the coupled neutron detectors by depositing 10B4C onto substrates made from different materials such as Al and glass which then coupled with silicon-based detectors. The responses of these neutron detectors to neutrons (Cf-252) were measured individually. It's showen that the detection capability of direct contact neutron detectors was lower than the coupled neutron detectors. For the coupled detectors, the detector by depositing 10B4C on the aluminum substrate was found to be superior than that by depositing 10B4C on the glass substrate.