Publications by authors named "Ahmed A Al-Tabbakh"

The significance of the Fowler-Nordheim-type plots lies in the possibility of extracting useful and reliable physical parameters of the field electron emitters. This is achieved by the parameter's extraction methods. We report on the application of two parameters extraction methods on field emission data from bundles of carbon fibers (CFs) grouped in nickel tubes and operated inside a typical field emission microscope setup.

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The behavior of the Folwer-Nordheim (FN) plot is investigated for large-area emitters arrays composed of perfectly aligned single-walled carbon nanotubes (CNTs). The field emission currents are calculated based on the standard FN model using the Murphy-Good equation. The aspect ratio of the CNTs is varied such that the height of the CNT has predefined uniform or Gaussian distributions.

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Hybrid heterojunction thin films, based on poly-(3-octylthiophene) (P3OT) polymer and oleic acid (OA)-capped cadmium selenide (CdSe) nanoparticles (NPs) are prepared by a spin-coating method. The structural and morphological properties of the CdSe NPs and of the hybrid thin films are investigated. The results of the dielectric characterization show that conductivity of the hybrid thin films is dependent on frequency and CdSe NP concentration.

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The Fowler - Nordheim (FN) plot behavior is investigated for field emitted electrons from virtual carbon nanotubes (CNTs)-based large area field emitters (LAFEs) arrays. The field emission currents are calculated using the Murphy-Good field emission equation assuming emission from two sets of geometrically-different CNTs. No screening effects are considered in the calculations.

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Field emission measurements of current-voltage characteristics are reported for tetrapod structures of ZnO. The nonlinear Fowler-Nordheim (FN) plot is analyzed according to a model of calculation based on saturation of conduction band current and predominance of valence band current at high-field values. The simulated FN plot exhibits similar features to those observed experimentally.

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