Field Emission from Nanocrystalline Diamond/Carbon Nanowall Composite Films Deposited on Scratched Substrates

2012 ◽  
Vol 1395 ◽  
Author(s):  
C.Y. Cheng ◽  
M. Nakashima ◽  
K. Teii
Keyword(s):  
Field Emission ◽  
Enhancement Factor ◽  
Composite Films ◽  
Diamond Films ◽  
Field Enhancement ◽  
Nanocrystalline Diamond ◽  
Field Emission Properties ◽  
Turn On ◽  
Carbon Nanowalls ◽  
Wall Spacing

ABSTRACTWe report the deposition and field emission properties of nanostructured composites consisting of carbon nanowalls (CNWs) and nanocrystalline diamond films by introducing two kinds of substrate scratching pretreatment, i.e., undulation and ultrasonic vibration. With increasing duration of scratching pretreatment, the morphology of the deposits changes from simple CNWs to a film/CNW composite and lastly to CNWs on a film, and then the space between the walls is increased. The emission turn-on field is reduced from 2.1 V/μm for simple CNWs to around 1.2 V/μm for the composite films, accompanied by an increase in field enhancement factor. The results indicate that electric field screening between the walls is successfully suppressed by widening of the wall spacing.

Synthesis of Carbon–Nitrogen Nanostructures by Hot Isostatic Pressure Apparatus and Their Field Emission Properties

2007 ◽  
Vol 7 (2) ◽  
pp. 570-574
Author(s):  
Yang Doo Lee ◽  
V. D. Blank ◽  
D. V. Batov ◽  
S. G. Buga ◽  
Yun-Hi Lee ◽  
...  
Keyword(s):  
Field Emission ◽  
Field Enhancement ◽  
Glass Frit ◽  
Gas Mixture ◽  
Nitrogen Gas ◽  
Field Emission Properties ◽  
Turn On ◽  
Field Emitters ◽  
Enhancement Factors ◽  
Resistive Heater

Carbon–nitrogen (CN) nanofibers were synthesized in argon–nitrogen gas mixture at 75 MPa by high isostatic pressure (HIP) apparatus using a graphite resistive heater. The CN nanofibers were grown in random with the diameter of about 200 nm and the length over 5 μm. The structures obtained can be divided bamboo-like, spring-like, and bead necklace-like CN nanofibers. The nitrogen content of up to 8.4% was found in CN nanofibers by EELS analysis. Field emission results showed that the density of field emitters and the field enhancement factors changed by surface treatments and that CN nanofibers contained glass frit. The screen-printed CN nanofiber had a turn-on field of 2 V/μm.

scholarly journals Microconical Structure Formation and Field Emission From Atomically Heterogeneous Surfaces Created by Microwave Plasma–Based Low-Energy Ion Beams

2021 ◽  
Vol 9 ◽  
Author(s):  
Jayashree Majumdar ◽  
Sudeep Bhattacharjee
Keyword(s):  
Work Function ◽  
Field Emission ◽  
Enhancement Factor ◽  
Field Enhancement ◽  
Ion Beams ◽  
Emission Current ◽  
Force Microscopy ◽  
Field Emission Properties ◽  
Argon Ion ◽  
Local Work

We report the formation of self-organized microconical arrays on copper surface when exposed to high flux (5.4 × 1015 cm−2 s−1) of 2 keV argon ion beams at normal incidence. The created microconical arrays are explored for field emission properties. The surface morphologies are investigated by scanning electron microscopy and atomic force microscopy. The local work function variation is analyzed by Kelvin probe force microscopy, and the argon content in the irradiated layer is measured with X-ray Photoelectron Spectroscopy. The average aspect ratio (base width/height) of microstructures for individual irradiated samples is found to increase from 0.7 to 1.5 with a decrease in ion fluence. The ion concentration is highest (3.89 %) for a fluence of 4.7 × 1018 cm−2, which asserts the formation of atomically heterogeneous surface due to subsurface ion implantation. An enhancement in the field emission properties of the argon ion–treated copper substrates at a fluence of 4.7 × 1018 cm−2 with a low turn-on voltage of 2.33 kV and with electron emission current 0.5 nA has been observed. From the Fowler–Nordheim equations, the field enhancement factor is calculated to be 5,561 for pristine copper, which gets enhanced by a factor of 2–8 times for irradiated substrates. A parametric model is considered, by taking into account the modified local work function caused due to structural undulations of the microstructures and presence of implanted argon ions, for explaining the experimental results on the field enhancement factor and emission current.

Field Emission Site Densities of Nanostructured Carbon

2001 ◽  
Vol 675 ◽  
Author(s):  
J B Cui ◽  
J Robertson ◽  
W I Milne
Keyword(s):  
Field Emission ◽  
Applied Field ◽  
Enhancement Factor ◽  
Field Enhancement ◽  
Carbon Films ◽  
Vacuum Arc ◽  
Nanostructured Carbon ◽  
Field Emission Properties ◽  
Site Density ◽  
Enhancement Factors

ABSTRACTThe field emission properties of nanostructured carbon films deposited by cathodic vacuum arc in a He atmosphere have been studied by measuring the emission currents and the emission site density. The films have an onset field of ∼3 V/μm. The emission site density is viewed on a phosphor anode and it increases rapidly with applied field. It is assumed that the emission occurs from surface regions with a range of field enhancement factors but with a constant work function. The field enhancement factor is found to have an exponential distribution.

Template synthesis of metal tungsten nanowire bundles with high field electron emission performance

RSC Advances ◽  
2016 ◽  
Vol 6 (67) ◽  
pp. 62668-62674 ◽  
Author(s):  
Yong Liu ◽  
Kun Lan ◽  
Mahir H. Es-Saheb ◽  
Ahmed A. Elzatahry ◽  
Dongyuan Zhao
Keyword(s):  
Field Emission ◽  
Template Synthesis ◽  
Electron Emission ◽  
Enhancement Factor ◽  
High Field ◽  
Field Enhancement ◽  
Field Electron Emission ◽  
Field Enhancement Factor ◽  
Emission Performance ◽  
Turn On

A H2 reduction-assisted hard-templating approach is demonstrated to synthesize metallic W nanowire bundles. The W nanowire bundles show a low turn-on field of 4.1 V μm−1, a high field enhancement factor up to 3563 and good field emission stability.

Fabrication and Field Emission Properties of Poly-CuTAPc Nanowires and Nanotubes

2009 ◽  
Vol 62 (9) ◽  
pp. 1007 ◽  
Author(s):  
Feng Gu ◽  
Chorng Haur Sow ◽  
Guo Qin Xu ◽  
Siau Gek Ang
Keyword(s):  
Field Emission ◽  
Enhancement Factor ◽  
Monomer Concentration ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Maximum Current Density ◽  
Turn On ◽  
Field Emitters ◽  
Maximum Current ◽  
Organic Nanomaterials

Poly-copper tetraaminophthalocyanine (CuTAPc) nanowires and nanotubes were successfully fabricated on porous anodic aluminium oxide (AAO) templates by electropolymerization and characterized. The product of electropolymerization, whether as nanowires or nanotubes, is a function of the monomer concentration and template pore size. The morphology and field emission properties of these nanostructures were studied for investigation of potential application as field emitters. They show interesting turn-on field, maximum current density and enhancement factor, comparable to many other organic nanomaterials.

Electron Field Emission from GaN Nanotip Pyramids

2003 ◽  
Vol 798 ◽  
Author(s):  
Hock M. Ng ◽  
Jonathan Shaw ◽  
Aref Chowdhury ◽  
Nils G. Weimann
Keyword(s):  
Field Emission ◽  
Enhancement Factor ◽  
Molecular Beam ◽  
Field Enhancement ◽  
Electron Field Emission ◽  
Polar Regions ◽  
Turn On ◽  
Electron Field ◽  
Selective Chemical ◽  
20 Nm

ABSTRACTElectron field emission was measured from GaN nanotip pyramids formed by polarity-selective chemical etching in KOH solution. The GaN samples were grown by plasma-assisted molecular beam epitaxy and consisted of regions of Ga- and N-polar GaN grown at the same time. The pyramids were formed only in the N-polar regions and have extremely sharp tips with diameters estimated to be less than 20 nm. Field emission measurements showed a characteristic Fowler-Nordheim behavior. The average turn-on field was 1.6 V/μm with a corresponding normalized field enhancement factor of about 1500.

Effect of Catalyst Thickness and Plasma Pretreatment on the Growth of Carbon Nanotubes and Their Field Emission Properties

2007 ◽  
Vol 7 (11) ◽  
pp. 3731-3735 ◽  
Author(s):  
Hyung Soo Uh ◽  
Sang Sik Park ◽  
Byung Whan Kim
Keyword(s):  
Carbon Nanotubes ◽  
Field Emission ◽  
Field Enhancement ◽  
Close Relation ◽  
Emission Current Density ◽  
Ni Catalyst ◽  
Emission Characteristics ◽  
Field Emission Properties ◽  
Turn On ◽  
Plasma Pretreatment

We demonstrated that the diameter and the density of carbon nanotubes (CNTs) which had a close relation to electric-field-screening effect could be easily changed by the control of catalytic Ni thickness combined with NH3 plasma pretreatment. Since the diameter and the density of CNTs had a tremendous impact on the field-emission characteristics, optimized thickness of catalyst and application of plasma pretreatment greatly improved the emission efficiency of CNTs. In the field emission test using diode-type configuration, well-dispersed thinner CNTs exhibited lower turn-on voltage and higher field enhancement factor than the densely-packed CNTs. A CNT film grown using a plasma-pretreated 25 Å-thick Ni catalyst showed excellent field emission characteristics with a very low turn-on field of 1.1 V/μm @ 10 μA/cm2 and a high emission current density of 1.9 mA/cm2 @ 4.0 V/μm, respectively.

Field emission properties of spinel ZnCo2O4 microflowers

RSC Advances ◽  
2015 ◽  
Vol 5 (7) ◽  
pp. 5372-5378 ◽  
Author(s):  
Satyajit Ratha ◽  
Ruchita T. Khare ◽  
Mahendra A. More ◽  
Ranjit Thapa ◽  
Dattatray J. Late ◽  
...  
Keyword(s):  
Field Emission ◽  
Enhancement Factor ◽  
Field Enhancement ◽  
Field Enhancement Factor ◽  
Emission Performance ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Field Emission Performance ◽  
Facile Route

Spinel ZnCo2O4 microflowers were synthesized by a facile route and their field emission properties were studied in detail. They showed intriguing Field emission performance in terms of good field-enhancement factor and stability.

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