Microstructure control and property switching in stress-free van der Waals epitaxial VO2 films on mica Show others and affiliations
2023 (English) In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 229, article id 111864Article in journal (Refereed) Published
Abstract [en]
Realizing stress-free inorganic epitaxial films on weakly bonding substrates is of importance for applications that require film transfer onto surfaces that do not seed epitaxy. Film-substrate bonding is usually weakened by harnessing natural van der Waals layers (e.g., graphene) on substrate surfaces, but this is difficult to achieve in non-layered materials. Here, we demonstrate van der Waals epitaxy of stress-free films of a non-layered material VO2 on mica. The films exhibit out-of-plane 010 texture with three inplane orientations inherited from the crystallographic domains of the substrate. The lattice parameters are invariant with film thickness, indicating weak film-substrate bonding and complete interfacial stress relaxation. The out-of-plane domain size scales monotonically with film thickness, but the in-plane domain size exhibits a minimum, indicating that the nucleation of large in-plane domains supports subsequent island growth. Complementary ab initio investigations suggest that VO2 nucleation and van der Waals epitaxy involves subtle polarization effects around, and the active participation of, surface potassium atoms on the mica surface. The VO2 films show a narrow domain-size-sensitive electrical-conductiv ity-temperature hysteresis. These results offer promise for tuning the properties of stress-free van der Waals epitaxial films of non-layered materials such as VO2 through microstructure control (C) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Place, publisher, year, edition, pages ELSEVIER SCI LTD , 2023. Vol. 229, article id 111864
Keywords [en]
vad der Waals epitaxy; Thin films; X-ray diffraction; Electronic properties
National Category
Materials Chemistry
Identifiers URN: urn:nbn:se:liu:diva-196915 DOI: 10.1016/j.matdes.2023.111864 ISI: 001029199200001 OAI: oai:DiVA.org:liu-196915 DiVA, id: diva2:1791941
Note Funding Agencies|Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoeping University [2009 00971]; Swedish Research Council [2021-03826, 2021-04426]; Swedish Energy Agency [46519-1]; Knut and Alice Wallenberg foundation through the Wallenberg Academy Fellows program [KAW-2020.0196]; Linkoeping Electron Microscopy Laboratory; Swedish Foundation for Strategic Research (SSF) [RIF 14-0074]; French government program "Investissements dAvenir" [ANR-18-EURE-0010, ANR-11-LABX-0017-01]; US National Science Foundation [CMMI 2135725]
2023-08-282023-08-282024-01-19