Design and Analysis of High-k Dielectric Super junction Schottky Barrier Diodes Beyond Unipolar Figure of Merit

Abstract

<p>This study presents design guidelines for a high-k dielectric Superjunction Schottky barrier diode (SBD) to further enhance the already impressive unipolar power figure of merit (PFOM) of Ultra-wide bandgap (UWBG) materials. We employed analytical modeling to optimize the device parameters, accounting for the appropriate dielectric and semiconductor dimensions including the aspect ratio and the dielectric constant of the highk material. Our findings reveal that device performance is intimately linked to structural dimensions and the dielectric constant of the insulator. Specifically, we observed that the dielectric superjunction SBD exhibits behavior akin to a conventional SBD, where the effective doping density in the drift layer decreases by a factor dependent on semiconductor and dielectric width, aspect ratio and the dielectric constant of the insulator. We discuss optimal design guidelines for achieving a 10 kV β-Ga<sub>2</sub>O<sub>3</sub> SBD with a PFOM of 50 GW/cm<sup>2</sup>, a significant improvement over the conventional unipolar PFOM of 34 GW/cm<sup>2</sup> for β-Ga<sub>2</sub>O<sub>3</sub>. Additionally, we conducted a comparative analysis of the switching energies between the superjunction Schottky barrier diode and a conventional Schottky barrier diode.We provide design guidelines to minimize switching energies for a desired PFOM in β-Ga<sub>2</sub>O<sub>3</sub> SBDs. This underscores the immense potential of such structures in advancing vertical power electronics to unprecedented levels of performance.</p>