SiO₂/ Si₃N₄ Electret Incorporated AlN Substrates for Partial Discharge Free WBG Power Electronics Operating at Low Pressures

Electrets are dielectric materials capable of generating electric fields without a voltage source. Previous studies have focused on the design, fabrication, and utilization of electrets to counter and neutralize locally concentrated high electric fields and mitigate partial discharge (PD) in power electronics systems. However, the effectiveness of inorganic electrets in mitigating PD in low-pressure conditions has remained unexplored. Here, we present results showing that $\mathrm{SiO}_{2} / \mathrm{Si}_{3} \mathbf{N}_{4}$ thin film electrets exhibit notable efficacy in mitigating PD and increasing partial discharge inception voltage (PDIV) at low pressures. Index Terms- $\mathrm{SiO}_{2} / \mathrm{Si}_{3} \mathbf{N}_{4}$, thin film, electret, partial discharge (PD), low pressure, power electronics, packaging.