Thermal neutron detection with pyrolytic boron nitride

Commercially acquired samples of pyrolytic boron nitride (pBN) were tested as potential thermal neutron detectors. The pBN material has a high content of 10B (19.9% natural abundance), allowing for the excitation of charge carriers from the 10B(n,α)7Li reaction. Samples 5 mm×5 mm×1 mm thick with conductive contacts applied to both sides were operated as traditional planar semiconductor detectors. Being a solid, the material is attractive as a possible solid-state neutron detector. The devices were tested in a diffracted neutron beam from a nuclear reactor. Experimental results from the prototype devices are reported.