2300V Reverse Breakdown Voltage Ga2O3 Schottky Rectifiers

We report field-plated Schottky rectifiers of various dimensions (circular geometry with diameter 50200 mu m and square diodes with areas 4 A 10(3)10(2) cm(2)) fabricated on thick (20 mu m), lightly doped (n 2.10 A 10(15) cm(3)) beta-Ga2O3 epitaxial layers grown by Hydride Vapor Phase Epitaxy on conducting (n 3.6 A 10(18) cm(3)) substrates grown by Edge-Defined, Film-Fed growth. The maximum reverse breakdown voltage (V-B) was 2300V for a 150 mu m diameter device (area 1.77 A 10(4) cm(2)), corresponding to a breakdown field of 1.15 MV.cm(1). The reverse current was only 15.6 mu A at this voltage. This breakdown voltage is highest reported for Ga2O3 rectifiers. The on-state resistance (R-ON) for these devices was 0.25 Omega.cm(2), leading to a figure of merit (V-B(2)/R-ON) of 21.2 MW.cm(2). The Schottky barrier height of the Ni was 1.03 eV, with an ideality factor of 1.1 and a Richardson's constant of 43.35 A.cm(2).K-2 obtained from the temperature dependence of the forward current density. The breakdown voltages for the different size devices ranged from 14002300V, with a general, but not linear trend of decreasing breakdown voltage for larger area rectifiers. The reverse recovery time was similar to 22 ns for switching from +2 V to 2 V. (C) 2018 The Electrochemical Society.