High current lateral gan transistors with scalable topology and gate drive phase equalization

Abstract

Large area, high current, lateral GaN power transistors are implemented using an on-chip interconnect topology wherein the transistor is arranged as an array of sections, each section comprising a set of transistor islands; gate and source buses that form each gate drive loop have substantially the same track widths; the source bus runs over or under the gate bus, and the tracks are inductively coupled to provide flux cancellation in the gate drive loop, thereby reducing parasitic inductances. The gate delay in each gate drive loop is reduced, minimizing the gate drive phase difference across the transistor. An overlying current redistribution layer preferably has a track width no greater than that of the underlying source and drain buses, for efficient coupling. This topology provides improved scalability, enabling fabrication of multi-section, large scale, high current lateral GaN transistors with reduced gate drive loop inductance, for improved operational stability.