ENHANCING VERTICAL GA₂O₃ POWER DEVICES VIA CURRENT BLOCKING LAYER INNOVATION

Abstract

Beta-gallium oxide (β-Ga₂O₃) has emerged as a compelling material for next-generation power electronics, owing to its ultra-wide bandgap of 4.8 eV and high critical electric field of 8 MV/cm. These properties, along with the availability of melt-grown substrates, position β-Ga₂O₃ as a key contender for high-voltage device applications. However, the lack of effective p-type doping—due to highly localized holes and large acceptor activation energies—presents a major challenge to implementing traditional n–p–n vertical power transistors. To address this limitation, recent research has focused on the integration of a current-blocking layer (CBL), which can replicate the role of a p-type region in vertical device architectures. This perspective reviews the progress in CBL-based designs within vertical β-Ga₂O₃ MOSFETs and highlights emerging concepts such as the Mg-diffused CBL for enabling vertical diffused barrier field-effect transistors (VDBFETs). The potential of CBL technology to overcome the doping bottleneck and enable scalable, high-performance vertical devices is discussed