This paper introduces a growth method---suboxide molecular-beam epitaxy (S-MBE)---which enables the growth of Ga2O3 and related materials at growth rates exceeding 1 micrometer per hours with excellent crystallinity in an adsorptioncontrolled regime. Using a Ga + Ga2O3 mixture with an oxygen mole fraction of x(O) = 0.4 as an MBE source, we overcome kinetic limits that had previously hampered the adsorption-controlled growth of Ga2O3 by MBE. We present growth rates up to 1.6 micrometer per hour for Ga2O3--Al2O3 heterostructures with unprecedented crystalline quality and also at unparalleled low growth temperature for this level of perfection. We combine thermodynamic knowledge of how to create molecular-beams of targeted suboxides with a kinetic model developed for the S-MBE of III-VI compounds to identify appropriate growth conditions. Using S-MBE we demonstrate the growth of phase-pure, smooth, and high-purity homoepitaxial Ga2O3 films that are thicker than 4 micrometer. With the high growth rate of S-MBE we anticipate a significant improvement to vertical Ga2O3-based devices. We describe and demonstrate how this growth method can be applied to a wide-range of oxides. S-MBE rivals leading synthesis methods currently used for the production of Ga2O3-based devices.
@article{arxiv.2011.00084,
title = {Adsorption-Controlled Growth of Ga2O3 by Suboxide Molecular-Beam Epitaxy},
author = {Patrick Vogt and Felix V. E. Hensling and Kathy Azizie and Celesta S. Chang and David Turner and Jisung Park and Jonathan P. McCandless and Hanjong Paik and Brandon J. Bocklund and Georg Hoffman and Oliver Bierwagen and Debdeep Jena and Huili G. Xing and Shin Mou and David A. Muller and Shun-Li Shang and Zi-Kui Liu and Darrell G. Schlom},
journal= {arXiv preprint arXiv:2011.00084},
year = {2024}
}