Ultrafast Switching of GaN Transistors for Nanosecond Pulse Generation

Due to their smaller parasitic components, gallium nitride high-electron-mobility transistors (GaN HEMTs) are faster than their silicon counterparts. Therefore, they are suitable for applications that require ultrafast switching including plasma generation, where the faster rise time of the applied high-voltage and high-current pulses leads to a higher yield. The gate driver circuit and its implementation determine the turn-on process of the GaN transistors. Therefore, this article investigates two different gate drivers based on the LMG1020 gate driver integrated circuit (IC), previously used for silicon and silicon carbide transistors, to reduce the turn-on time of GaN transistors. In the proposed methods, the switching performance of a 650 V transistor has been evaluated in pulsed operation with a resistive load of 610 V and 107 A. The obtained rise time results for the monolithic Si-based and voltage-source gate drivers are 4.23 and 2.92 ns, respectively.