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Field Emission Properties (field + emission_property)
Selected AbstractsThe Growth of One-Dimensional Single-Crystalline AlN Nanostructures by HVPE and Their Field Emission Properties,CHEMICAL VAPOR DEPOSITION, Issue 1-3 2010Yun-Ki Byeun Abstract Single-crystalline AlN nanostructures, such as thin films, nanoneedles, nanocolumns, and nanowires, depending on the controlled gas-flow ratio, are synthesized by halide vapor-phase epitaxy (HVPE). In comparison with a typical vapor/liquid/solid (VLS) mechanism for the growth of nanowires, well-aligned AlN nanorod arrays with diameters below 20,nm are grown on a catalyst-free Si substrate though a vapor/solid (VS) mechanism. Their structural and optical properties are measured by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL). In particular, AlN nanorods exhibit an excellent field emission property with a low turn-on field of 2.25,V,µm,1. The field enhancement factor is estimated to be about 784 due to well-aligned, needle-shaped, AlN nanorods. [source] Influence of the electric field on BN conical structuresINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 8 2006Sérgio Azevedo Abstract We apply first-principles calculations to investigate the effect of the electric field on boron nitride conical structures. The studies involve nanocones with different disclination angles. We applied fields of 0.3 V/Å and 0.6 V/Å parallel to the cone axis. It is shown that a small field does not affect the stability of such structures; however, for a larger field, a decrease of 0.1 eV/atom for all structures is observed. We also find modification in the energy gap due to the intensity of the electric field. The bandgap decreased proportionally to the intensity of the electric field, indicating that these results have consequences in the field emission properties of these structures. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [source] Diamond plates on dome-like particles: preparation, characterization and field emission propertiesJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2010Rajanish N. Tiwari Thin diamond microplates have been grown on dome-like/hemispherical carbon particles on titanium carbide by a microwave plasma chemical vapour deposition (MPCVD) method using a gas mixture of methane and hydrogen. The diamond microplates have a thickness of about 200,nm. A thin (300,nm) film of titanium carbide was formed during carburization of sputtered titanium on an Si(100) substrate in MPCVD. The hemispherical carbon particles were covered with diamond microplates. The diamond microplates are isolated electron-emitting spherules and exhibit a low threshold (50,V,µm,1) and high current density (0.92,mA,cm,2) in their field emission properties. A possible mechanism for the formation of the diamond microplates and hemispherical carbon particles is presented. [source] The Growth of One-Dimensional Single-Crystalline AlN Nanostructures by HVPE and Their Field Emission Properties,CHEMICAL VAPOR DEPOSITION, Issue 1-3 2010Yun-Ki Byeun Abstract Single-crystalline AlN nanostructures, such as thin films, nanoneedles, nanocolumns, and nanowires, depending on the controlled gas-flow ratio, are synthesized by halide vapor-phase epitaxy (HVPE). In comparison with a typical vapor/liquid/solid (VLS) mechanism for the growth of nanowires, well-aligned AlN nanorod arrays with diameters below 20,nm are grown on a catalyst-free Si substrate though a vapor/solid (VS) mechanism. Their structural and optical properties are measured by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL). In particular, AlN nanorods exhibit an excellent field emission property with a low turn-on field of 2.25,V,µm,1. The field enhancement factor is estimated to be about 784 due to well-aligned, needle-shaped, AlN nanorods. [source] | ||||||||||