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Title: Electron gun using carbon-nanofiber field emitter

Abstract

An electron gun constructed using carbon-nanofiber (CNF) emitters and an electrostatic Einzel lens system has been characterized for the development of a high-resolution x-ray source. The CNFs used were grown on tungsten and palladium tips by plasma-enhanced chemical-vapor deposition. Electron beams with the energies of 10<E<20 keV were focused by the electrostatic lens and impinged on a W target for x-ray radiography. Analyzing the recorded x-ray radiographs, the focal spot size of the electron beam extracted from the CNFs was estimated to be D<50 {mu}m in diameter. Superior performance was realized by using CNFs with larger fiber radii (100-500 nm) grown sparsely on the metal tips, which were installed in a holder at the short length L=0.5 mm.

Authors:
; ; ; ; ; ;  [1];  [2]
  1. Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20953235
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 1; Other Information: DOI: 10.1063/1.2430650; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CARBON; CARBON FIBERS; CHEMICAL VAPOR DEPOSITION; ELECTRON BEAMS; ELECTRON GUNS; ELECTRONS; ELECTROSTATIC LENSES; FIELD EMISSION; KEV RANGE; NANOSTRUCTURES; PALLADIUM; PERFORMANCE; TUNGSTEN; X RADIATION; X-RAY RADIOGRAPHY; X-RAY SOURCES

Citation Formats

Sakai, Y., Haga, A., Sugita, S., Kita, S., Tanaka, S.-I., Okuyama, F., Kobayashi, N., and Toshiba Corporation, 8 Shinsugita-cho, Isogo-ku, Yokohama 235-8523. Electron gun using carbon-nanofiber field emitter. United States: N. p., 2007. Web. doi:10.1063/1.2430650.
Sakai, Y., Haga, A., Sugita, S., Kita, S., Tanaka, S.-I., Okuyama, F., Kobayashi, N., & Toshiba Corporation, 8 Shinsugita-cho, Isogo-ku, Yokohama 235-8523. Electron gun using carbon-nanofiber field emitter. United States. doi:10.1063/1.2430650.
Sakai, Y., Haga, A., Sugita, S., Kita, S., Tanaka, S.-I., Okuyama, F., Kobayashi, N., and Toshiba Corporation, 8 Shinsugita-cho, Isogo-ku, Yokohama 235-8523. Mon . "Electron gun using carbon-nanofiber field emitter". United States. doi:10.1063/1.2430650.
@article{osti_20953235,
title = {Electron gun using carbon-nanofiber field emitter},
author = {Sakai, Y. and Haga, A. and Sugita, S. and Kita, S. and Tanaka, S.-I. and Okuyama, F. and Kobayashi, N. and Toshiba Corporation, 8 Shinsugita-cho, Isogo-ku, Yokohama 235-8523},
abstractNote = {An electron gun constructed using carbon-nanofiber (CNF) emitters and an electrostatic Einzel lens system has been characterized for the development of a high-resolution x-ray source. The CNFs used were grown on tungsten and palladium tips by plasma-enhanced chemical-vapor deposition. Electron beams with the energies of 10<E<20 keV were focused by the electrostatic lens and impinged on a W target for x-ray radiography. Analyzing the recorded x-ray radiographs, the focal spot size of the electron beam extracted from the CNFs was estimated to be D<50 {mu}m in diameter. Superior performance was realized by using CNFs with larger fiber radii (100-500 nm) grown sparsely on the metal tips, which were installed in a holder at the short length L=0.5 mm.},
doi = {10.1063/1.2430650},
journal = {Review of Scientific Instruments},
number = 1,
volume = 78,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
  • A fine-focusing x-ray source has been constructed employing a field electron emitter prepared by growing carbon-nanofibers (CNFs) on a metal tip. The x-ray source is composed of a CNF field electron emitter, an electrostatic lens, two magnetic lenses, and a W-target for generating x-rays by electron impact. The CNFs provided field electrons with a current density of J{approx}5x10{sup 9} A/m{sup 2}, which was evaluated with the aid of Fowler-Nordheim theory. The electron beam extracted from the CNF emitter was accelerated to the energies of E=10-25 keV, and then focused by the lenses. By recording the x-ray images of test charts,more » the optimum resolution of the x-ray source was estimated to be approximately D{sub x}=0.5 {mu}m.« less
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