Silicon Carbide Neutron Detectors for Harsh Nuclear Environments: A Review of the State of the Art

Abstract

Silicon carbide (SiC) semiconductor is an ideal material for solid-state nuclear radiation detectors to be used in high-temperature, high-radiation environments. Such harsh environments are typically encountered in nuclear reactor measurement locations as well as high-level radioactive waste and/or "hot" dismantling-decommissioning operations. In the present fleet of commercial nuclear reactors, temperatures in excess of 300 °C are often encountered, and temperatures up to 800 °C are anticipated in advanced reactor designs. The wide bandgap for SiC (3.27 eV) compared to more widely used semiconductors such as silicon (1.12 eV at room temperature) has allowed low-noise measurements to be carried out at temperatures up to 700 °C. The concentration of thermally induced charge carriers in SiC at 700 °C is about four orders of magnitude less than that of silicon at room temperature. Furthermore, SiC radiation detectors have been demonstrated to be much more resistant to the effects of radiation-induced damage than more conventional semiconductors such as silicon, germanium, or cadmium zinc telluride (CZT), and have been demonstrated to be operational after extremely high gamma-ray, neutron, and charged-particle doses. The purpose of the present review is to provide an updated state of the art for SiC neutron detectors and to explore their applications in harsh high-temperature, highradiation nuclear reactor applications. Conclusions related to the current state-of-the-art of SiC neutron detectors will be presented, and specific ideal applications will be discussed.

Low-Temperature Annealing of Electron, Neutron, and Proton Irradiation Effects on SiC Radiation Detectors

“…Recently, the growth of commercial interest for power applications has made available larger SiC substrates (up to 8-in diameter wafers) and high quality chemical vapor-deposited epitaxial layers [9,10]. SiC is currently one of the most attractive semiconductor materials for radiation detectors to be operated in harsh radiation environments and high-temperature conditions, particularly, for alpha particle detection in plasma diagnostic systems for future nuclear fusion reactors [11][12][13]. Consequently, special interest in the study of radiation effects on SiC technologies has grown-up in the recent years.…”

Design Considerations for Boron-Diffused and Implanted 4H-SiC Epitaxial Neutron Detectors for Dosimetry and Monitoring Applications

“…Following the first demonstration of radiation detectors based on 4H-SiC epitaxial layers [2], rapid progress and refinement of SiC detectors have been achieved [3][4][5][6][7]. SiC neutron detectors are particularly useful for measurements in the high-temperature, high-radiation environments typically encountered in nuclear power applications [8]. The wide bandgap (3.27 eV at 300K) results in far fewer thermally generated charge carriers compared to conventional lower bandgap semiconductors such as silicon or germanium and allows operation in elevated-temperature environments up to 700 °C without the need for cooling.…”

Fabrication and characterization of high-resolution 4H-SiC epitaxial radiation detectors for challenging reactor dosimetry environments

“…Also, 4H-SiC is the only wide bandgap semiconductor whose native oxide is SiO2, making it compatible with the matured silicon device fabrication technology. The unique combination of the above properties makes 4H-SiC the ideal and future material for electronic devices in harsh environments [8]. 4H-SiC epitaxial layers have been demonstrated as versatile high-resolution radiation detectors which are equally capable of detecting energetic charged particles as well as penetrating radiation such as neutrons and gamma rays [9] [10] [11] [12] [13] [14].…”