Transport properties of ultra-thin VO{sub 2} films on (001) TiO{sub 2} grown by reactive molecular-beam epitaxy

Journal Article · Mon Oct 19 00:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4932123· OSTI ID:22485941

Paik, Hanjong; Tashman, Joshua W. ^[1]; Moyer, Jarrett A.; Schiffer, Peter ^[2]; Spila, Timothy ^[3]; Mundy, Julia A. ^[4]; Freeman, Eugene; Shukla, Nikhil; Datta, Suman ^[5]; Lapano, Jason M.; Engel-Herbert, Roman ^[6]; Zander, Willi; Schubert, Jürgen ^[7]; Muller, David A. ^[4]

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1. Department of Material Science and Engineering, Cornell University, Ithaca, New York 14853 (United States)
2. Department of Physics, University of Illinois Urbana-Champaign, Urbana, Illinois 61801 (United States)
3. Materials Research Laboratory, University of Illinois Urbana-Champaign, Urbana, Illinois 61801 (United States)
4. School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853 (United States)
5. Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
6. Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
7. Peter Grünberg Institute (PGI9-IT), JARA-Fundamentals of Future Information Technologies, Research Centre Jülich, D-52425 Jülich (Germany)

We report the growth of (001)-oriented VO{sub 2} films as thin as 1.5 nm with abrupt and reproducible metal-insulator transitions (MIT) without a capping layer. Limitations to the growth of thinner films with sharp MITs are discussed, including the Volmer-Weber type growth mode due to the high energy of the (001) VO{sub 2} surface. Another key limitation is interdiffusion with the (001) TiO{sub 2} substrate, which we quantify using low angle annular dark field scanning transmission electron microscopy in conjunction with electron energy loss spectroscopy. We find that controlling island coalescence on the (001) surface and minimization of cation interdiffusion by using a low growth temperature followed by a brief anneal at higher temperature are crucial for realizing ultrathin VO{sub 2} films with abrupt MIT behavior.

• OSTI ID: 22485941
• Journal Information: Applied Physics Letters, Vol. 107, Issue 16; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CATIONS
COALESCENCE
ENERGY-LOSS SPECTROSCOPY
FILMS
LAYERS
MOLECULAR BEAM EPITAXY
PHASE TRANSFORMATIONS
SUBSTRATES
SURFACES
TITANIUM OXIDES
TRANSMISSION ELECTRON MICROSCOPY
VANADIUM OXIDES