Advanced Electro-Thermal Modeling of Edge Termination in Diamond and Ultra-Wide Bandgap Power Devices

Traditional design and optimisation of Si-based power devices rely on quasi-static edge termination modelling that has proven to be effective in reproducing experimental results. However, this approach fails to accurately describe emerging wideand ultra-wide-bandgap power devices operating in fast-switching environments, such as in automotive applications, where devices are subject to rapid voltage and over-current transients (dV/dt > 100 V/ns). The absence of a robust design methodology that captures the transient electro-thermal response of the semiconductor, oxide, and passivation layers often results in devices that underperform in real operating conditions. This work addresses this longstanding challenge by introducing a comprehensive dynamic simulation framework that reproduces key aspects of dynamic reverse-bias (DRB) testing used for automotive qualification. Using a diamond-based Schottky barrier diode as a case study, we demonstrate that conventional quasi-static and time-dependent simulation strategies lead to markedly different design outcomes. The proposed transient approach captures the interplay between field redistribution, charge trapping, and self-heating effects, offering enhanced predictive accuracy and robustness for the next generation of power devices.