Plasma-Assisted Molecular Beam Epitaxy 1

Abstract

Plasma-assisted molecular beam epitaxy has been used to grow the highest quality β-Ga2O3 thin films and has shown potential to realize various efficient device structures. Growth of β-Ga2O3 is defined by the suboxide desorption that limits growth rates at high temperatures and Ga fluxes. Growth in various orientations has been demonstrated with the (010) b-plane in particular showing promise for homoepitaxy due to high realized growth rates and materials quality. N-type doping with Sn, Ge, and Si has allowed for device structures that utilize electron conduction in this materials system. Heterostructures with β-(AlxGa1-x)2O3 have been used for modulation doped field effect transistors; however, thermodynamic limitations of maximum achievable Al content have limited device performance. Expanding the growth regime through metal-oxide catalyzed epitaxy using In could help improve heterostructure growth for future devices.