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Title: Field emission from gadolinium silicide prepared by ion implantation with electron beam annealing

Abstract

A silicon-based field emission cathode, the rare earth silicide GdSi{sub 2} was prepared by implanting Gd ions into silicon using a metal vapor vacuum arc ion source and subsequently annealed by electron beam. For as-implanted samples, turn-on field was about 21 V/{mu}m at a current density of 1 {mu}A/cm{sup 2} and a field emission current density of 1 mA/cm{sup 2} was reached at an applied field of 34 V/{mu}m. After annealing, the turn-on field could be as low as 9 V/{mu}m and the current density of 1 mA/cm{sup 2} can be reached at an applied field of 14 V/{mu}m. X-ray diffraction with x-ray photoelectron spectroscopy analyses and atomic force microscopy were used to characterize microstructure changes of the samples. The results showed that these excellent field emission characteristics were attributed to the GdSi{sub 2} compounds formed in the samples. The field emission mechanism was discussed in terms of Fowler-Nordheim (FN) theory. It was found that FN plots could be divided into two segments obviously, and this was perhaps because of the thermal effect in the process of field emission.

Authors:
; ;  [1]
  1. School of Physical Science and Technology, Lanzhou University, Lanzhou 730000 (China)
Publication Date:
OSTI Identifier:
20982776
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 6; Other Information: DOI: 10.1063/1.2654773; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; ATOMIC FORCE MICROSCOPY; CATHODES; CURRENT DENSITY; ELECTRON BEAMS; FIELD EMISSION; GADOLINIUM IONS; GADOLINIUM SILICIDES; ION IMPLANTATION; ION SOURCES; MICROSTRUCTURE; SILICON; VAPORS; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Duan, H. G., Xie, E. Q., and Ye, F. Field emission from gadolinium silicide prepared by ion implantation with electron beam annealing. United States: N. p., 2007. Web. doi:10.1063/1.2654773.
Duan, H. G., Xie, E. Q., & Ye, F. Field emission from gadolinium silicide prepared by ion implantation with electron beam annealing. United States. doi:10.1063/1.2654773.
Duan, H. G., Xie, E. Q., and Ye, F. Thu . "Field emission from gadolinium silicide prepared by ion implantation with electron beam annealing". United States. doi:10.1063/1.2654773.
@article{osti_20982776,
title = {Field emission from gadolinium silicide prepared by ion implantation with electron beam annealing},
author = {Duan, H. G. and Xie, E. Q. and Ye, F.},
abstractNote = {A silicon-based field emission cathode, the rare earth silicide GdSi{sub 2} was prepared by implanting Gd ions into silicon using a metal vapor vacuum arc ion source and subsequently annealed by electron beam. For as-implanted samples, turn-on field was about 21 V/{mu}m at a current density of 1 {mu}A/cm{sup 2} and a field emission current density of 1 mA/cm{sup 2} was reached at an applied field of 34 V/{mu}m. After annealing, the turn-on field could be as low as 9 V/{mu}m and the current density of 1 mA/cm{sup 2} can be reached at an applied field of 14 V/{mu}m. X-ray diffraction with x-ray photoelectron spectroscopy analyses and atomic force microscopy were used to characterize microstructure changes of the samples. The results showed that these excellent field emission characteristics were attributed to the GdSi{sub 2} compounds formed in the samples. The field emission mechanism was discussed in terms of Fowler-Nordheim (FN) theory. It was found that FN plots could be divided into two segments obviously, and this was perhaps because of the thermal effect in the process of field emission.},
doi = {10.1063/1.2654773},
journal = {Journal of Applied Physics},
number = 6,
volume = 101,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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