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Title: Space charge limited current emission for a sharp tip

Abstract

In this paper, we formulate a self-consistent model to study the space charge limited current emission from a sharp tip in a dc gap. The tip is assumed to have a radius in the order of 10s nanometer. The electrons are emitted from the tip due to field emission process. It is found that the localized current density J at the apex of the tip can be much higher than the classical Child Langmuir law (flat surface). A scaling of J ∝ V{sub g}{sup 3/2}/D{sup m}, where V{sub g} is the gap bias, D is the gap size, and m = 1.1–1.2 (depending on the emission area or radius) is proposed. The effects of non-uniform emission and the spatial dependence of work function are presented.

Authors:
;  [1]
  1. Engineering Product Development, Singapore University of Technology and Design, Singapore 487372 (Singapore)
Publication Date:
OSTI Identifier:
22410286
Resource Type:
Journal Article
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 22; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1070-664X
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CURRENT DENSITY; ELECTRONS; FIELD EMISSION; SPACE CHARGE; SPACE DEPENDENCE; WORK FUNCTIONS

Citation Formats

Zhu, Y. B., E-mail: zhuyingbin@gmail.com, and Ang, L. K., E-mail: ricky-ang@sutd.edu.sg. Space charge limited current emission for a sharp tip. United States: N. p., 2015. Web. doi:10.1063/1.4919936.
Zhu, Y. B., E-mail: zhuyingbin@gmail.com, & Ang, L. K., E-mail: ricky-ang@sutd.edu.sg. Space charge limited current emission for a sharp tip. United States. doi:10.1063/1.4919936.
Zhu, Y. B., E-mail: zhuyingbin@gmail.com, and Ang, L. K., E-mail: ricky-ang@sutd.edu.sg. Fri . "Space charge limited current emission for a sharp tip". United States. doi:10.1063/1.4919936.
@article{osti_22410286,
title = {Space charge limited current emission for a sharp tip},
author = {Zhu, Y. B., E-mail: zhuyingbin@gmail.com and Ang, L. K., E-mail: ricky-ang@sutd.edu.sg},
abstractNote = {In this paper, we formulate a self-consistent model to study the space charge limited current emission from a sharp tip in a dc gap. The tip is assumed to have a radius in the order of 10s nanometer. The electrons are emitted from the tip due to field emission process. It is found that the localized current density J at the apex of the tip can be much higher than the classical Child Langmuir law (flat surface). A scaling of J ∝ V{sub g}{sup 3/2}/D{sup m}, where V{sub g} is the gap bias, D is the gap size, and m = 1.1–1.2 (depending on the emission area or radius) is proposed. The effects of non-uniform emission and the spatial dependence of work function are presented.},
doi = {10.1063/1.4919936},
journal = {Physics of Plasmas},
issn = {1070-664X},
number = 5,
volume = 22,
place = {United States},
year = {2015},
month = {5}
}