Growth and phase transition characteristics of pure M-phase VO2 epitaxial film prepared by oxide molecular beam epitaxy

Abstract

VO2 epitaxial film with large size has been prepared by oxide-molecular beam epitaxy method on Al2O3 (0001) substrate. The VO2 film shows a perfect crystal orientation, uniformity, and distinct metal-insulator phase transition (MIT) characteristics. It is observed that the MIT character is closely associated with the crystal defects such as oxygen vacancies. By controlling the growth condition, the MIT temperature can be tuned through modifying the content of oxygen vacancies. The role of the oxygen vacancies on the phase transition behavior of this VO2 film is discussed in the framework of the hybridization theory and the valence state of vanadium.

Resistance switching of epitaxial VO2/Al2O3 heterostructure at room temperature induced by organic liquids

“…Both of these peaks exhibited six-fold symmetry, 33,35,36 which agrees with the crystal symmetry of the VO 2 and Al 2 O 3 . Furthermore, 33,36 To study the organic-liquid-modulated transport properties of the VO 2 film, we measured the I-V curves of the VO 2 /Al 2 O 3 heterostructure in a two-probe configuration at room temperature. As shown in Fig.…”

Dynamically tracking the joule heating effect on the voltage induced metal-insulator transition in VO2 crystal film

“…11,24 Combined with the AFM image as well as the X-ray reflectance curve in Figure S2, 25 we can conclude that the VO 2 film sample prepared by the OMBE method has very high quality.…”

“…The details of the epitaxial film preparation were reported elsewhere. 24 The X-ray diffraction (XRD) and X-ray reflectance spectroscopy (XRR) experiments were performed at the Shanghai Synchrotron Radiation Facility (SSRF 14B station). The X-ray photoemission spectroscopy (XPS) and X-ray absorption near-edge spectroscopy (XANES) were conducted at the National Synchrotron Radiation Laboratory (NSRL), Hefei.…”

Nanoscale Phase Separation and Lattice Complexity in VO2: The Metal–Insulator Transition Investigated by XANES via Auger Electron Yield at the Vanadium L23-Edge and Resonant Photoemission

“…High-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images were taken on a JEM ARM200F (JEOL Ltd., Tokyo, Japan) with a probe aberration corrector, while the diffraction pattern was acquired on a JEM 2100 TEM (JEOL Ltd., Tokyo, Japan). More details of the epitaxial film preparation, performed at the University of Science and Technology (Hefei, China), are reported elsewhere [36].…”