skip to main content

Title: Appearance of large crystalline domains in VO{sub 2} films grown on sapphire (001) and their phase transition characteristics

We report the first observation of large crystalline domains of several μm-size in VO{sub 2} films deposited on Al{sub 2}O{sub 3} (001) substrates by rf-biased reactive sputtering technique. The large crystalline domains, dominated with random in-plane oriented growth of (011){sub M1}-orientation, appear only under adequate substrate biasing, such as 10 W, while most biasing conditions result in conventional nanosized grains of highly oriented (010){sub M1}-orientation. Two temperature-controlled analyses, x-ray diffraction and micro-Raman spectroscopy, have revealed that some parts of large crystalline domains undergo intermediate monoclinic (M2) phase during the thermally-induced structural phase transition from monoclinic (M1) to rutile-tetragonal (R) phase. As an effect of the appearance of large crystalline domains, the film showed in-plane tensile stress, resulting in high T{sub IMT} of 69 °C due to the elongation of the V-V distance in its low-temperature monoclinic phase.
Authors:
; ;  [1] ; ;  [2]
  1. Graduate School of Science and Technology, Tokai University, Hiratsuka 259-1292 (Japan)
  2. GREMAN, UMR 7347 CNRS, Université François Rabelais de Tours, Parc de Grandmont 37200 Tours (France)
Publication Date:
OSTI Identifier:
22490741
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 24; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINIUM OXIDES; FILMS; MONOCLINIC LATTICES; NANOSTRUCTURES; PHASE TRANSFORMATIONS; RAMAN SPECTROSCOPY; RANDOMNESS; RUTILE; SAPPHIRE; SPUTTERING; STRESSES; SUBSTRATES; VANADIUM OXIDES; X-RAY DIFFRACTION