Study on single event burnout mechanism on the “step current” of SiC schottky diodes

Abstract

Single event burnout (SEB) causes catastrophic failure to SiC power devices for power applications in space. The electrical behavior of the 4H-SiC Schottky Barrier Diode (SBD) exposed to heavy ion radiation is investigated using the Sentaurus Technical Computer Aided Design (TCAD) simulations. A “step current” is observed when the reverse current increases under heavy ion irradiation and the simulation results show the dependence of SEB on applied bias voltage, linear energy transfer (LET), and incidence angles of the heavy ion. In addition, the femto-second pulsed laser SEE facility (FPLSEE) are carried out to study the SEB characteristic of SiC SBD. The experiment results were similar to those obtained from the simulation. The electron density distribution, impact ionization distribution, and recombination distribution for SiC SBD are used to understand the possible single event burnout (SEB) mechanism involved. Results show that the SEB process in SiC SBD has both avalanche amplification respectively triggered by impact ionization and carriers recombination, and the “step” trend emerges when the two achieve dynamic equilibrium.