Enhancing the Radiation Hardness of Vertical 4h–sic Detectors by the Metal-Oxide-semiconductor Structure

In this work, 4H–SiC α-particle detectors with metal/semiconductor (MS) and metal/oxide/semiconductor (MOS) structures have been fabricated. The effects of introducing a SiO2 dielectric layer to form a MOS structure on the electrical properties, the performances, and the radiation hardness of the detectors have been evaluated systematically by comparing those with the MS structure. It is found that the reverse leakage current and the signal-to-noise ratio of α-particle detectors at high voltages can be improved by the MOS structure. Furthermore, the MOS structure exhibits much higher radiation hardness, as the energy resolution degradation of α particle detectors with MOS and MS structures after the γ irradiation is 0.59% and 2.87%, respectively. This work may provide a way to enhance the radiation hardness of 4H–SiC α-particle detectors.