Enhancement-Mode GaN Monolithic Bidirectional Switch With Breakdown Voltage Over 3.3 kV

This work demonstrates a GaN enhancement-mode monolithic bidirectional switch (MBDS) with breakdown voltage (BV) higher than 3.3 kV in both polarities. This MBDS is realized on a dual p-GaN gate high electron mobility transistor (HEMT) platform on sapphire substrate. It features a novel dual junction termination extension design for electric field management, which is built on the p-GaN layer in the gate stack and does not require epitaxial regrowth. The GaN MBDS exhibits symmetric on-state characteristics in both directions with a threshold voltage $({V}_{\text {th}})$ of 0.6 V and a low specific on-resistance $({R}_{\text {on,sp}})$ of 5.6 m $\Omega \cdot $ cm2. This device presents the highest BV, as well as one of the best BV and ${R}_{\text {on,sp}}$ trade-offs, in all the reported MBDS devices. The ${R}_{\text {on,sp}}$ is lower than the performance limit of conventional BDS realized by two discrete devices. This 3.3 kV GaN MBDS opens the door for developing new circuit topologies and advancing system performance in medium-voltage power electronics.