Review on interface engineering of low leakage current and on-resistance for high-efficiency Ga2O3-based power devices
Chowdam Venkata Prasad, You Seung Rim
Abstract
Beta-Gallium oxide (β-Ga 2 O 3 ) has emerged as a very feasible semiconductor material for new explorations, thanks to its advantages of ultra-wide bandgap and diverse material systems. The high breakdown electric field, high working temperature, and excellent Baliga's figure-of-merit (BFOM) of β-Ga 2 O 3 represent an inspiring outlook of power electronic devices. β-Ga 2 O 3 -based materials and devices have been increasingly popular in recent years for power electronics, owing to their ability to generate high-quality bulk substrates at a low cost. In this review article, we describe the recent investigations on the interface engineering of the β-Ga 2 O 3 -based power devices. Meanwhile, different methods for enlightening the performances including breakdown voltage and on-resistance have been summarized. Improved ohmic connections by reducing contact resistance through interfacial engineering and interlayers such as conducting oxides of AZO, ITO , and related materials, as well as the development of selective ion implantation doping. Some solutions to problematic challenges, such as p-type doping difficulty and low thermal conductivity , are also provided and addressed. Transferring devices to another substrate or thinning down the substrate and using heat sinks as well as top-side heat extraction could help to mitigate the low thermal conductivity . The ion-cutting process for heterogeneous integration of a β-Ga 2 O 3 thin film with a highly thermally conductive substrate is an innovative technology for overcoming β-Ga 2 O 3 weak thermal conductivity in nature and realizing β-Ga 2 O 3 full potential in power electronics. Finally, the viewpoint of β-Ga 2 O 3 -based devices for power electronic applications has been analyzed.