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

Abstract

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 10 B and 6 LiF, 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 10 B 4 C film in various forms. The 10 B 4 C 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 10 B 4 C directly onto the front surface of silicon-based detectors; (2) the other was the coupled neutron detectors by depositing 10 B 4 C 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 10 B 4 C on the aluminum substrate was found to be superior than that by depositing 10 B 4 C on the glass substrate.