MBE of Gallium Oxide: Material Development for Future Devices
Akhil Mauze, Graduate Student Researcher, Speck Group
UCSB Materials Department
Following the progress of wide bandgap semiconductors like GaN and SiC for power switching applications, new ultrawide bandgap materials have emerged as potential candidates. β-Gallium Oxide (β-Ga2O3) has gained attention due to large breakdown field (> 5 MV/cm), large bandgap (4.8 eV), and availability of scalable substrates grown from a melt with relatively low dislocation density (104 cm-2). Recent β-Ga2O3 research has yielded growth by various epitaxial and bulk techniques as well as demonstration of early devices.
Controllable doping and heterostructures with Aluminum and Indium allow for a variety of unipolar device designs, but materials investigation is still in the early stages. In this talk I will review our recent progress at UCSB on growth and doping of β-Ga2O3 and its heterostructures via plasma-assisted molecular beam epitaxy. Additionally, I will discuss a unique catalytic growth mechanism of β-Ga2O3 with Indium that provides new opportunities in growth space to potentially achieve better devices.