Crucible aperture: an effective way to reduce source oxidation in oxide molecular beam epitaxy process

Abstract

Growing multi-elemental complex-oxide structures using an MBE (Molecular Beam Epitaxy) technique requires precise control of each source flux. However, when the component elements have significantly different oxygen affinities, maintaining stable fluxes for easily oxidizing elements is challenging because of a source oxidation problem. Here, using Sr as a test source, we show that a crucible aperture insert scheme significantly reduces the source oxidation in an oxide-MBE environment. The crucible aperture insert was shaped like a disk with a hole at the center and was mounted inside the crucible; it blocks most of the oxygen species coming to the source, thus reducing the source oxidation. However, the depth of the aperture disk was critical for its performance; an ill-positioned aperture could make the flux stability even worse. With an optimally positioned aperture insert, the crucible exhibited more than four times improvement in Sr flux stability, compared to a conventional, non-apertured crucible.

13 pages, 3 figures

References in corpus (1)

• Sr flux stability against oxidation in oxide-MBE environment: flux, geometry, and pressure dependence

Cited by in corpus (4)

• Epitaxial growth of topological insulator Bi2Se3 film on Si(111) with atomically sharp interface
• Simple self-gettering differential-pump for minimizing source oxidation in oxide-MBE environment
• Towards controllable Si-doping in oxide molecular beam epitaxy using a solid SiO source: Application to $\beta$-Ga2O3
• Correlating surface stoichiometry and termination in SrTiO${}_3$ films grown by hybrid molecular beam epitaxy