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We report on response of newly designed 4H-SiC Schottky barrier diode (SBD) detector to alpha, beta and gamma particles. In order to optimize SiC SBD detector’s thermal neutron efficiency, it’s of particular importance to understand its behavior in various radiation fields. The optimal size of the SBD is limited by degradation of electronic properties, and consequently their charge particle detection. We have manufactured diodes up to 3 x 3 mm active surface area to study those properties in correlation with increasing of detector size. Approximately 25 µm thick epitaxial layer is grown on SiC substrate by chemical vapor deposition, which is sufficient to stop alpha particles up to 6.8 MeV. Different active volume sizes of the detector based have been electrically characterized and exposed to radiation fields of alpha, beta and gamma particles. Extensive studies of the detector response to the various alpha emitters in the 3.27 MeV to 8.79 MeV energy range have been carried out. Results presented here demonstrate not only excellent linear response of the different detector active area to alpha particles, but also shows linear response to gamma particles. The detectors show a linear energy response, high charge collection efficiency and high energy resolution for the alpha particle energies bellow 6.7 MeV which is in a correlation with the range of charged particles in epitaxial layer of our detectors. Electrical characteristics of the detectors were assessed by temperature dependent current-voltage (I-V) and capacitance-voltage (C-V) measurements as well as by Laplace DLTS characterization of the electrically active defects. Ideality factor of the diodes is found to be in the range of 1.01 to 1.02 and free carrier concentration is in the range of 3x1014 cm-3 to 4.5x1014 cm-3. Co-60 and Cs-137 gamma radiations were carried out in Ruđer Bošković Institute’s Secondary Standard Dosimetry Laboratory with the air kerma rates up to 77 mGy/min., The 7th International Conference on Advancements in Nuclear Instrumentation Measurement Methods and their Applications (ANIMMA2021)

In 2016, the NATO Science for Peace and Security Programme funded research project "Engineering SiliconCarbide for Border and Port Security" — E-SiCure was launched, its objective being the development ofradiation-hard silicon carbide (SiC) based detectors of special nuclear materials (SNM), with the aim to enhanceborder and port security barriers. Detector prototypes based on SiC Schottky Barrier Diodes (SBDs) and neutronconverter films were developed. This paper presents the results of a dedicated experimental testing campaignperformed at the Jožef Stefan Institute (JSI) TRIGA reactor in which several SiC detector prototypes equippedwith10B and6LiF converter films were irradiated in the Dry Chamber of the reactor. The obtained resultsdemonstrate a clearly measurable neutron response, which varies linearly with the neutron flux. The measuredparticle spectra from the SiC detectors exhibit a clear structure, attributable to the nature and energy ofsecondary particles originating as reaction products from nuclear reactions involving10B and6Li isotopes.The determined sensitivity of the detectors, their active volume being 1 mm×1 mm×25μm, 1 mm×1 mm×69μmand 1 mm×1 mm×170μm, was of the order of 2×10−5counts per second, per unit ofneutron flux [counts s−1per n cm−2s−1] (for neutron energies between 0 and 5 eV). Scaling the detectionsensitivity by a factor of105, i.e. to an array with a surface of around 20 cm×2 m, comparable to largeBF3or3He detectors, would theoretically enable an overall sensitivity of around 2 counts s−1per n cm−2s−1,which is already comparable to typical neutron sensitivity values of gas detectors, in the range from severalto over 100 counts s−1per n cm−2s−1. Due to its outstanding tolerance to harsh environments (including hightemperatures and radiation fields) and superior electronic properties when compared to other semiconductors,SiC is a promising base material for the fabrication of solid-state detectors with stable and long life-time.Improvements in sensitivity combined with the capability of fabricating large modules (SiC arrays), couldmake SiC an important detection technology, applicable also in the context of border and port security barriermonitoring.