For decades, silicon-based power transistors (MOSFETs, field-effect transistors) formed the backbone of power conversion systems that convert alternating current (AC) into direct current (DC) and vice versa, or DC from low voltage to high voltage and vice versa. In the quest for alternatives that can drive up the switching speed, gallium nitride (GaN) quickly came forward as one of the leading candidate materials. The GaN/AlGaN materials system exhibits a higher electron mobility and higher critical electric field for breakdown. Combined with the high electron mobility transistor (HEMT) architecture, it results in devices and ICs that feature higher breakdown strength, faster switching speed, lower conductance losses and a smaller footprint than comparable silicon solutions.
Source : Monolithic integration of GaN components boosts power integrated circuits