1700 V Breakdown Monolithic Bidirectional GaN/AlGaN MISHEMTs with a Thin Buffer Grown on SiC Substrate

We present the performances of our GaN MISHEMTs, using a thin buffer grown on SiC substrate, to pave the way for lateral GaN devices to exploit power applications in the voltage range up to 1700 V. Uni- and bi-directional MISHEMTs based on gate and source-connected field plate, with LGD = 21 µm achieve a breakdown voltage over 1800 V at a drain-source and gate currents less than 50 nA/mm. The on-resistance of the 1 mm gate width uni and bidirectional devices were 9.5 Ω∙mm and 13.5 Ω∙mm, respectively, with a specific on-resistance of 2.7 mΩ∙cm2 and 4.4 mΩ∙cm2, respectively. The 1mm single MISHEMT
results in a high Baliga figure of merit (BFOM) of 1.2 GW/cm2. A 147 mm gate width MISHEMT delivered 20 A pulse IDS current, at VGS =0 V and VDS = 1.5 V. Moreover, the MISHEMTs feature encouraging and superior stand in the breakdown voltage vs. on-resistance benchmark to commercial devices. We addressed the potential of the GaN-HEMTs to cover applications demanding breakdown voltages > 1200 V.