Publication detail
Fabrication and Electrical Characterization of Dot Capacitors for Cold Field Emission Applications
Alsoud, A. Shaheen, AA. Knápek, A. Al-Bashaish, SR. Ahmad, MDJ. Mousa, MS. Sobola, D.
Original Title
Fabrication and Electrical Characterization of Dot Capacitors for Cold Field Emission Applications
Type
journal article in Web of Science
Language
English
Original Abstract
The aim of this work was to study the dielectric properties of dot capacitors composed of a microtip coated with a thin layer of epoxy resin bonded to a steel plate. Two microtips with radii ranging from 3 to 5 mu m were fabricated via electrochemical etching and coated with an epoxy layer 27-35 mu m in thickness. The microtips were characterized by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). This study showed that composite cold-field emission emitters behave as dot capacitors. The real and imaginary parts of the impedance and permittivity, along with the direct and alternating conductivities, activation energies, and hopping energies, were examined. These evaluations were conducted at temperatures of 30, 45, 60, 75, and 90 degrees C, with a frequency range of 1 to 106 Hz using impedance spectroscopy. The results indicated that both the impedance and electrical permittivity decreased slightly with increasing temperature, whereas the AC conductivity was independent of temperature. Additionally, a decrease in the activation and jump energies was observed as the thickness of the epoxy layer increased. The low values of the activation and hopping energies facilitated electron transport through the epoxy layer. The modified hopping model also provides an explanation for the conduction mechanism through the epoxy layer. The Nyquist plot shows that the capacitance decreased with increasing temperature. A slight increase in relaxation time was also observed, indicating the onset of conductive pathway formation. These findings contribute to a better understanding of the capacitance of the composite emitters and the formation of conductive pathways.
Keywords
CONDUCTIVITY; TIPS; COMPOSITES; RESIN
Authors
Alsoud, A.; Shaheen, AA.; Knápek, A.; Al-Bashaish, SR.; Ahmad, MDJ.; Mousa, MS.; Sobola, D.
Released
14. 3. 2025
Publisher
AMER CHEMICAL SOC
Location
WASHINGTON
ISBN
2470-1343
Periodical
ACS OMEGA
Year of study
10
Number
11
State
United States of America
Pages from
11108
Pages to
11118
Pages count
11
URL
BibTex
@article{BUT197904,
author="Alexandr {Knápek} and Saleh R. {Al-Bashaish} and Dinara {Sobola} and Ammar {AL Soud} and Adel Ahmad ABD-ELHAFIZ {Shaheen} and M D (Assa’d) Jaber {Ahmad} and Marwan S. Mousa {Mousa}",
title="Fabrication and Electrical Characterization of Dot Capacitors for Cold Field Emission Applications",
journal="ACS OMEGA",
year="2025",
volume="10",
number="11",
pages="11108--11118",
doi="10.1021/acsomega.4c10081",
issn="2470-1343",
url="https://pubs.acs.org/doi/10.1021/acsomega.4c10081"
}