A simulation study of vertical Ga2O3 Schottky barrier diodes using field plate termination

Abstract

The precision design of beta-phase gallium oxide (β-Ga2O3) power devices requires appropriate physical properties, including a breakdown electric field intensity. To clarify the breakdown electric field in β-Ga2O3, we fabricated vertical Schottky barrier diodes (SBDs) with a field plate (FP) on a β-Ga2O3 (001) epitaxial layer and simulated their breakdown situations under reverse bias. The calculated breakdown voltages of the SBD with a single FP were consistent with the experimental values when assuming an electric field criterion of 5 MV cm−1 in β-Ga2O3. By designing a SBD with a double FP according to the electric field criterion above, a breakdown voltage over 2 kV and specific on-resistance of 6.9 mΩ cm2 were realized simultaneously. This results in an electric field criterion that is useful for the design parameter of β-Ga2O3 devices to balance a high breakdown voltage and low on-resistance.