MOVPE growth of AlGaN on RIE-treated GaN surfaces and its application to AlGaN/GaN electron devices

In this paper, we provide a comprehensive review of our studies on the metal–organic-vapor-phase-epitaxial (MOVPE) growth of AlGaN directly on reactive-ion-etched (RIE) GaN surfaces and its application to the fabrication of vertical and lateral enhancement (E)-mode AlGaN/GaN metal–insulator–semiconductor (MIS) high-electron-mobility transistors (HEMTs). First, the peculiarities and challenges of MOVPE growth of AlGaN on RIE-GaN surfaces and their countermeasures are described and discussed. Next, the fabrication of vertical trench E-mode MIS-HEMTs using AlGaN regrowth and their output characteristics are demonstrated. Finally, the recent results on lateral recessed-gate E-mode MIS-HEMTs are described.