Design of a Thin-Film Neutron Detector Used for Personnel Dosimeter

Abstract

Semiconductors used for neutron detector are always coated by a thin-film, which is used to convert free neutrons into charged particles. The thin-film commonly used in such detectors utilize the ¹⁰B(n, α)⁷Li reaction, the ⁶Li(n, α)³He reaction, or the recoil proton reaction. The detection efficiency of these detectors coated with single thin-film varied with the energy of neutrons. So the energy response performance of personnel dosimeter with these detectors is not satisfactory. The purpose of the article is designing a suitable neutron detector for personnel dosimeter. In order to overcome the disadvantage of the energy response performance the neutron detectors are coated by a single thin-film. In these designs a neutron personnel dosimeter detector fabricated with three silicon diodes are coated by two different thin-films. One silicon diode is uncoated and will be used to subtract the response to gamma rays of the coated silicon diodes. The response of each silicon diodes coated by different thin-films are calculated with Monte Carlo code MCNPX. The total personnel doserate results will be obtained by summing-up each response of the coated silicon diodes multiplied with different gain factors.