Spectral identification of thin-film-coated and solid-form semiconductor neutron detectors

Abstract

Semiconductor-based solid-state neutron detectors have received considerable attention in recent years. These devices can be categorized as either thin-film-coated diode detectors or solid-form bulk detectors. There have been many attempts to fabricate boron-based solid-form detectors utilizing processing techniques similar to those frequently used to fabricate thin-film-coated diodes. Consequently, results from attempts to fabricate boron-based semiconductor neutron detectors are often misinterpreted as solid-form detectors when in fact they are functioning as common thin-film-coated diodes. In principle, boron-based solid-form detectors should be able to achieve higher efficiencies for detecting thermal neutrons than can boron-based thin-film-coated diodes, but only if they are truly operating as solid-form bulk detectors. Hence, a method to distinguish between the two devices is necessary. In this paper, it is proposed that proper interpretation of the observed differential pulse-height spectra can provide the necessary discrimination between the two types of detectors. Modeled comparisons of differential pulse-height spectra between thin-film-coated devices and solid-form devices are presented, thereby providing assistance to researchers in the field to properly interpret experimental results.