Formation and phase transition of VO{sub 2} precipitates embedded in sapphire

Journal Article · Tue Jun 01 04:00:00 EDT 1999 · Journal of Materials Research

DOI:https://doi.org/10.1557/JMR.1999.0348· OSTI ID:354519

Gea, L A; Budai, J D; Boatner, L A ^[1]

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1. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

Crystallographically coherent precipitates of vanadium dioxide (VO{sub 2}) have been formed in the near-surface region of single crystals of sapphire (Al{sub 2}O{sub 3}) using a combination of ion implantation and thermal treatments. As in the case of either bulk VO{sub 2} single crystals or thin films of VO{sub 2}, the thermally induced semiconductor-to-metal phase transition of the embedded VO{sub 2} precipitates is accompanied by a large hysteretic change in the infrared optical transmission. The VO{sub 2} precipitate transition temperature (T{sub c}=72 to 85&hthinsp;{degree}C) is higher than that of bulk VO{sub 2} (T{sub c}=68&hthinsp;{degree}C) and is sensitive to the implantation conditions. The present results show that the damage resulting from the coimplantation of vanadium and oxygen into an Al{sub 2}O{sub 3} host lattice dictates the final microstructure of the VO{sub 2} precipitates and, consequently, affects the transition temperature, as well as the optical quality of the VO{sub 2}/Al{sub 2}O{sub 3} surface-nanocomposite precipitate system. {copyright} {ital 1999 Materials Research Society.}

• OSTI ID: 354519
• Journal Information: Journal of Materials Research, Journal Name: Journal of Materials Research Journal Issue: 6 Vol. 14; ISSN JMREEE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
INFRARED RADIATION
ION IMPLANTATION
LIGHT TRANSMISSION
MICROSTRUCTURE
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PRECIPITATION
SAPPHIRE
THIN FILMS
VANADIUM COMPOUNDS
VANADIUM OXIDES