A review of GaN HEMTs: Characteristics, parameter impacts, and strategies for oscillation suppression

Gallium nitride high electron mobility transistors (GaN HEMTs) have emerged as a promising class of power semiconductor switching devices due to their superior characteristics, and have been widely used in the applications requiring high frequency, high efficiency, and high power density. Despite these advantages, the low parasitic capacitance of GaN HEMTs makes them highly sensitive to the parasitic inductances in high-frequency circuits, leading to switching oscillations. These oscillations can induce adverse effects, including voltage and current overshoots, false triggering, electromagnetic interference, crosstalk, and additional power losses. A comprehensive review of GaN HEMTs is provided, focusing on their operational principles and electronic characteristics. It further examines the impacts of various parameters and discusses widely adopted methods for oscillation suppression. The aim is to offer practical insights for the design and optimization of GaN HEMT-based power systems.