Electron Irradiation Hardness of High-Voltage 4H-SiC Schottky Diodes in the Operating Temperature Range

Effect of irradiation with 0.9 MeV electrons on the parameters of 4H-SiC Schottky diodes with a limiting blocking voltage Ub = 600 and 1700 V was studied for the first time in the range of operating temperatures Ti (23 and 175°C). The range of fluences Φ was 1 × 1016–2 × 1016 cm–2 for devices with Ub = 600 V and 5 × 1015–1.5 × 1016 cm–2 for devices with Ub = 1700 V. Irradiation at room temperature increases significantly the differential resistance of the base of the diodes. Irradiation with the same doses at Ti = 175°C—i.e. at limiting operating temperature of devices, does not affect practically the parameters of current–voltage characteristics. Nevertheless, the DLTS spectra demonstrate a significant increase in the concentration of deep levels in the upper half of the band gap not only after irradiation at room temperature, but also after irradiation at Ti = 175°C.