Direct correlation of structural and electrical properties of electron-doped individual VO2nanowires on devised TEM grids
Autor: | Kim Mw, Bong-Joong Kim, Yong-Ryun Jo |
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Rok vydání: | 2016 |
Předmět: |
Materials science
business.industry Mechanical Engineering Electron energy loss spectroscopy Transition temperature Nanowire Bioengineering 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Optics Mechanics of Materials Transmission electron microscopy Rutile Electrical resistivity and conductivity Optoelectronics General Materials Science Electrical and Electronic Engineering 0210 nano-technology business High-resolution transmission electron microscopy Joule heating |
Zdroj: | Nanotechnology. 27:435704 |
ISSN: | 1361-6528 0957-4484 |
Popis: | Nano-scale VO2 wires with controlled parameters such as electron-doping have attracted intense interest due to their capability of suppressing the temperature of the metal-insulator transition (MIT). However, because their diameters are smaller than the spatial resolutions of the conventional measuring equipment, the ability to perform a thorough examination of the wires has been hindered. Here, we report the fabrication of a transmission electron microscopy (TEM) grid with an optimum design of Si3N4 windows on which the photolithography for individual electron-doped VO2 nanowire devices can be safely accomplished, allowing the cross-examination of the structural and electrical properties. TEM dark-field imaging was used to quantitatively investigate the fractions of rutile and M1 phases, and their lattice alignments were observed using high-resolution TEM (HRTEM) with small area diffraction. Moreover, electron energy loss spectroscopy (EELS) revealed that the rutile domain would be created by the strain induced by oxygen vacancies. Importantly, we successfully tuned the transition temperature by changing the rutile fraction while maintaining a high level of resistivity change. The resistivity at room temperature linearly decreased with the rutile fraction, following a simple model. Furthermore, the T dependence of the threshold voltage can be attributed to the Joule heating, exhibiting an identical thermal dependence, irrespective of the rutile fraction. |
Databáze: | OpenAIRE |
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