High Permittivity Dielectric Field-Plated Vertical (001) $\beta$-Ga$_2$O$_3$ Schottky Barrier Diode with Surface Breakdown Electric Field of 5.45 MV/cm and BFOM of $>$ 1 GW/cm$^{2}$

TL;DR

This paper reports a vertical $eta$-Ga$_2$O$_3$ Schottky barrier diode with a novel high permittivity dielectric field plate, achieving record surface breakdown electric field and high BFOM, suitable for high-voltage power applications.

Contribution

Introduction of a high permittivity dielectric field plate in $eta$-Ga$_2$O$_3$ SBDs to significantly enhance breakdown voltage and efficiency, with detailed device performance analysis.

Findings

Surface breakdown electric field of 5.45 MV/cm

Breakdown voltage of 687 V

BFOM of 1.47 GW/cm$^{2}$

Abstract

This paper presents vertical (001) oriented $\beta$-Ga$_2$O$_3$ field plated (FP) Schottky barrier diode (SBD) with a novel extreme permittivity dielectric field oxide. A thin drift layer of 1.7 $\mu m$ was used to enable a punch-through (PT) field profile and very low differential specific on-resistance (R$_{on-sp}$) of 0.32 m$\Omega$-cm$^{2}$. The extreme permittivity field plate oxide facilitated the lateral spread of the electric field profile beyond the field plate edge and enabled a breakdown voltage ($V_{br}$) of 687 V. The edge termination efficiency increases from 13.5 $\%$ for non-field plated structure to 63 $\%$ for high permittivity field plate structure. The surface breakdown electric field was extracted to be 5.45 MV/cm at the center of the anode region using TCAD simulations. The high permittivity field plated SBD demonstrated a record high Baliga figure of merit (BFOM) of 1.47 GW/cm$^{2}$ showing the potential of Ga$_2$O$_3$ power devices for multi-kilovolt class applications.