High-Temperature Static and Dynamic Reliability Study of 4H-SiC Vertical-Channel JFETs for High-Power System Applications
In this work we report the most recent high-temperature long-term reliability results of the 600 V/14 A, 4H-SiC vertical-channel junction field-effect transistors (VJFETs). Two groups (A and B) devices were subjected to different thermal and electrical stresses. One device (Group A) reached 12,000 hours of continuous switching without a single failure. Four devices in Group A were thermally stressed at 250 °C over 4,670 hours in air, for which standard deviation of the specific on-resistance (RONSP) in linear region at gate bias (VGS) of 3 V were < 4.1% throughout the entire duration time. The off-state characteristics were evaluated by high temperature reverse bias (HTRB) tests. Three devices (Group A) were biased at 50% rated BVDS at 250 °C for 2,278 hours. A higher reverse bias at 80 % rated BVDS was then applied to 14 devices (group B) at 200 °C for 1,000 hours. Variations of the leakage current were negligible throughout the entire HTRB test for all tested devices.
Akira Suzuki, Hajime Okumura, Tsunenobu Kimoto, Takashi Fuyuki, Kenji Fukuda and Shin-ichi Nishizawa
L. Cheng et al., "High-Temperature Static and Dynamic Reliability Study of 4H-SiC Vertical-Channel JFETs for High-Power System Applications", Materials Science Forum, Vols. 600-603, pp. 1051-1054, 2009