High breakdown voltage InAlN/AlN/GaN HEMTs achieved by Schottky-Source technology

In this paper, we demonstrate 253% improvement in the off-state breakdown voltage (BV) of the lattice-matched In
_0.17
Al
_0.83
N/GaN high-electron-mobility transistors (HEMTs) by using a new Schottky-Source technology. Based on this concept, the Schottky-Source (SS) InAlN/GaN HEMTs are proposed. The SS HEMTs with a L
_GD
of 15 μm showed a three-terminal BV of 650 V, while conventional InAlN/GaN HEMTs of the same geometry showed a maximum BV of 184 V. Without using any field-plate the result measured in the proposed device is the highest BV ever achieved on InAlN/GaN HEMTs. The corresponding specific on-resistance (R
_{sp, on}
) is as low as 3.4 mΩ·cm
²
. A BV of 118 V was also obtained in an SS InAlN/GaN HEMTs with L
_GD
=1 μm, which is the highest BV in GaN-based HEMTs featuring such a short L
_GD
with GaN buffer.