Optimizing diode thickness for thin-film solid state thermal neutron detectors

Abstract

In this work, we investigate the optimal thickness of a semiconductor diode for thin-film solid state thermal neutron detectors. We evaluate several diode materials, Si, CdTe, GaAs, C (diamond), and ZnO, and two neutron converter materials, 10B and 6LiF. Investigating a coplanar diode/converter geometry, we determine the minimum semiconductor thickness needed to achieve maximum neutron detection efficiency. By keeping the semiconductor thickness to a minimum, gamma rejection is kept as high as possible. In this way, we optimize detector performance for different thin-film semiconductor materials.

Advanced Nanomaterials for Nuclear Energy and Nanotechnology

“…Murphy et al investigated the optimal thickness of a semiconductor diode for thin‐film solid‐state thermal neutron detectors. They investigated a coplanar diode/converter geometry to determine the minimum semiconductor thickness needed to achieve maximum neutron detection efficiency.…”

Experimental determination of gamma-ray discrimination in pillar-structured thermal neutron detectors under high gamma-ray flux

“…Murphy et al reported that Si provides better gamma-ray rejection compared with other semiconductor materials, i.e. C (diamond), ZnO, GaAs, and CdTe [14].…”

Nevada National Security Site Site-Directed Research and Development FY 2014 Annual Report

“…Two categories of solid-state devices have been demonstrated in literature: indirect conversion and direct conversion heterostructures. Indirect conversion device geometries place a thin film of neutronsensitive material within range of, but external to, an adjacent space-charge layer (LiCausi 2008, Caruso 2010, Melton 2011, Dahal 2012, Murphy 2012. In contrast, direct conversion heterostructures contain a neutron-sensitive material that can also be the space-charge layer (Robertson 2002;Caruso 2006Caruso , 2010Hong 2010).…”