Title :
The effects of high-dose gamma irradiation on high-voltage 4H-SiC Schottky diodes and the SiC-SiO2 interface
Author :
Sheridan, David C. ; Chung, Gilyong ; Clark, Steve ; Cressler, John D.
Author_Institution :
Dept. of Electr. & Comput. Eng., Auburn Univ., AL, USA
fDate :
12/1/2001 12:00:00 AM
Abstract :
The effects of radiation on high-voltage 4H-SiC Schottky diodes for use in extreme environment power supplies are investigated for the first time. Diodes were fabricated with a wide range of barrier heights (1.06-1.60 eV) and were evaluated after being exposed to a 60Co gamma radiation source. DC current-voltage characteristics were measured after several radiation doses, with no observable degradation in the diode forward or reverse characteristics up to a total dose of 4 Mrad(Si). Measured breakdown voltages of post-irradiated diodes increase approximately 200 V compared to the virgin devices and are attributed to increased negative interface charge, as determined by MOS capacitor measurements and correlated with numerical breakdown simulations
Keywords :
MOS capacitors; Schottky diodes; gamma-ray effects; radiation hardening (electronics); semiconductor device breakdown; semiconductor device measurement; semiconductor device models; semiconductor-insulator boundaries; silicon compounds; wide band gap semiconductors; 200 V; DC current-voltage characteristics; MOS capacitor; SiC-SiO2; SiC-SiO2 interface; barrier heights; breakdown simulations; breakdown voltages; extreme environment power supplies; forward characteristics; gamma radiation source; high-dose gamma irradiation; high-voltage 4H-SiC Schottky diodes; negative interface charge; post-irradiated diodes; radiation; reverse characteristics; Breakdown voltage; Charge measurement; Current measurement; Current-voltage characteristics; Degradation; Gamma rays; MOS capacitors; Numerical simulation; Power supplies; Schottky diodes;
Journal_Title :
Nuclear Science, IEEE Transactions on
