Gamma and Proton Irradiation Effects on 4H-SiC Depletion-Mode Trench JFETs
4H-SiC vertical depletion-mode trench JFETs were fabricated, packaged, and then irradiated with either 6.8 Mrad gamma from a 60Co source, a 9x1011 cm-2 dose of 4 MeV protons, or a 5x1013 cm-2 dose of 63 MeV protons. 4H-SiC Schottky diodes were also fabricated, packaged and exposed to the same irradiations. The trench VJFETs have a nominal blocking voltage of 600 V and a forward current rating of 2 A prior to irradiation. On-state and blocking I-V characteristics were measured after irradiation and compared to the pre-irradiation performance. Devices irradiated with 4 MeV proton and gamma radiation showed a slight increase in on resistance and a decrease in leakage current in blocking mode. Devices irradiated with 63 MeV protons, however, showed a dramatic decrease in forward current. DLTS measurements were performed, and the results of these measurements will be discussed as well.
Dr. Roberta Nipoti, Antonella Poggi and Andrea Scorzoni
J. N. Merrett et al., "Gamma and Proton Irradiation Effects on 4H-SiC Depletion-Mode Trench JFETs", Materials Science Forum, Vols. 483-485, pp. 885-888, 2005