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 U-b = 600 and 1700 V was studied for the first time in the range of operating temperatures T-i (23 and 175(degrees)C). The range of fluences Phi was 1 <middle dot> 10(16)-2 <middle dot> 10(16) cm(-2) for devices with U-b = 600 V and 5 <middle dot> 10(15)-1.5 <middle dot> 10(16) cm(-2) for devices with U-b = 1700 V. Irradiation at room temperature increases significantly the differential resistance of the base of the diodes. Irradiation with the same doses at T-i = 175(degrees)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 T-i = 175(degrees)C.