Ion-Induced Energy Pulse Mechanism for Single-Event Burnout in High-Voltage SiC Power MOSFETs and Junction Barrier Schottky Diodes

Abstract

Heavy ion data suggest that a common mechanism is responsible for single-event burnout in 1200 V power MOSFETs and junction barrier Schottky diodes. Similarly, heavy ion data suggest a common mechanism is also responsible for leakage current degradation in both devices. This mechanism, based on ion-induced, highlylocalized energy pulses, is demonstrated in simulations and shown to be capable of causing degradation and singleevent burnout for both the MOSFETs and JBS diodes.

Unifying Concepts for Ion-Induced Leakage Current Degradation in Silicon Carbide Schottky Power Diodes

“…However, at 15 ps following the strike, the electric fields have been modified due to the ion-induced charge, and the shape and magnitude of each curve are identical, differing only in the location of the peak electric field, which, in each case, is at the epi/n+ junction. Further, the peak electric field at the epi/n+ junction is significantly higher than the electric field required for avalanche breakdown, generating additional carriers that can contribute to device damage [19]. As noted in Fig.…”

“…As noted in Fig. 6, the regions where the electric field varies rapidly are high resistance regions along the strike path (shown as L FRONT at the surface and L BACK at the epi/n+ interface), and denoted as L ION in [19]. The current density is high in these regions, resulting in high power dissipation.…”

“…2D TCAD models were developed in the Synopsys Sentaurus suite of TCAD tools [15] and used to explore the similarities of the heavy ion response between the SiC JBS Schottky diode device variants listed in Table I. Information for the 1200 V diode is primarily from published literature [16]- [19]. We have estimated the epitaxial depth and doping density from the breakdown voltage rating.…”

“…5, resulting in a resistive shunt across the device. As presented in [19], the damage to the device has likely occurred during or immediately following (within 100 ps) the strike. The power dissipation during the ion strike can be analyzed by taking 1D cut-lines along the ion track at various times following the strike.…”

Heavy-Ion Microbeam Studies of Single-Event Leakage Current Mechanism in SiC VD-MOSFETs

“…SiC power MOSFETs are also sensitive to single-event burnout. Numerous experiments and simulations have been performed to study the SEB in SiC power devices for space and terrestrial environments [10]- [19]. Due to the similarities in results on SiC MOSFETs and diodes, it has been hypothesized that the conventional SEB mechanisms developed in Si MOSFETs, such as parasitic bipolar transistor and tunneling-assisted avalanche multiplication mechanism [20], may be suppressed in SiC devices.…”