Silicon carbide radiation detector for harsh environments

Abstract

We used commercial off-the-shelf (COTS) silicon carbide (SiC) ultraviolet photodiodes for measuring gamma dose rates at high temperature. We tested them with Co-60 gamma dose rates between 0.03 mGy(Air)/s and 3 Gy(Air)/s. The diodes show excellent sensitivity, high signal-to-noise ratio (SNR), and good linearity. They were operated at temperatures up to 200 degrees C with negligible changes of the dark and the radiation-induced current. Gamma irradiation up to a total dose of 1080 kGy(Air), 32-MeV proton irradiations up to a fluence of 8.5 x 10/sup 12/ cm/sup -2/, and 14-MeV neutron irradiations up to 4.1 x 10/sup 12/ cm/sup -2/ demonstrate their radiation hardness. These results and the ability to measure the proton as well as the neutron dose rate after a calibration with Co-60 gammas show that COTS SiC diodes can be used as radiation detectors in harsh environments

Dose Rate Linearity in 4H-SiC Schottky Diode-Based Detectors at Elevated Temperatures

“…The data in the figure also show that the increase in the leakage current through the detector is correlated to the increase in the detected current (current signal in the figure) and the level of the magnitude of this correlation decreases significantly between 75 and 100 • C, indicating the practical limit on the upper operating temperature of the detector. Similar trend of increasing leakage current at 100 • C operating temperature has been observed previously in 4H-SiC and 6H-SiC [16], [37]. Dose rate linearity values can be extracted from the gradient of a linear fit to the current signal as a function of the incident dose rate.…”

“…8 as a function of applied bias and temperature. The data show that the dose rate linearity for D2 increases with increasing applied bias up to 120 V and it is relatively constant at temperatures below 100 • C. This temperature stability is due to the extremely low intrinsic carrier concentration in SiC, which arises from the wide bandgap, in comparison to conventional lower bandgap semiconductor materials such as silicon or gallium arsenide [37]. This is the property of SiC that makes it capable of operating in high temperature applications without the requirements of external cooling.…”

The effects of intense gamma-irradiation on the alpha-particle response of silicon carbide semiconductor radiation detectors

“…Metzger et al [6] observed no change in the 60 Co gamma detection efficiency for commercially available 6H-SiC photodiodes following 60 Co gamma-irradiations up to 1.080 MGy.…”

High-Dose Electron Radiation and Unexpected Room-Temperature Self-Healing of Epitaxial SiC Schottky Barrier Diodes

“…Thus, SiC-based structures have recently regained significant attention in advanced device applications. Furthermore, owing to its large intrinsic fundamental band gap (up to 3.26 eV [ 3 ]), SiC is not suitable to visible and infrared light stimulation or irradiation, and their radiation resistance is stronger than that of the conventional semiconductors (such as Si-based materials); therefore, SiC-based diodes are very promising candidates to replace silicon devices for atomic battery light sensors, nuclear cell photosensors [ 4 , 5 ], or particle detectors [ 6 , 7 ].…”