Use of the concept “area efficiency of emission” in equations describing field emission from large-area electron sources

2009 ◽  
Vol 27 (3) ◽  
pp. 1200 ◽  
Author(s):  
Richard G. Forbes
Keyword(s):  
Field Emission ◽  
Large Area ◽  
Electron Sources ◽  
Area Efficiency ◽  
Concept Area

A Stable Field Emission Electron Source

1977 ◽  
Vol 35 ◽  
pp. 58-59
Author(s):  
W.R. Bottoms ◽  
G.B. Haydon
Keyword(s):  
Field Emission ◽  
Signal To Noise Ratio ◽  
High Brightness ◽  
Electron Sources ◽  
Brightness Field ◽  
Current Densities ◽  
Properties Of Materials ◽  
Stable Field ◽  
Stable Current ◽  
Careful Design

There is great interest in improving the brightness of electron sources and therefore the ability of electron optical instrumentation to probe the properties of materials. Extensive work by Dr. Crew and others has provided extremely high brightness sources for certain kinds of analytical problems but which pose serious difficulties in other problems. These sources cannot survive in conventional system vacuums. If one wishes to gather information from the other signal channels activated by electron beam bombardment it is necessary to provide sufficient current to allow an acceptable signal-to-noise ratio. It is possible through careful design to provide a high brightness field emission source which has the capability of providing high currents as well as high current densities to a specimen. In this paper we describe an electrode to provide long-lived stable current in field emission sources.The source geometry was based upon the results of extensive computer modeling. The design attempted to maximize the total current available at a specimen.

scholarly journals Carbon Nanotube Electron Sources: From Electron Beams to Energy Conversion and Optophononics

2014 ◽  
Vol 2014 ◽  
pp. 1-23 ◽  
Author(s):  
Alireza Nojeh
Keyword(s):  
Carbon Nanotubes ◽  
Field Emission ◽  
Electron Emission ◽  
Electron Beams ◽  
Thermionic Emission ◽  
Secondary Emission ◽  
Electron Sources ◽  
Field Emitters ◽  
Electron Microscopes ◽  
Electron Emitters

Carbon nanotubes have a host of properties that make them excellent candidates for electron emitters. A significant amount of research has been conducted on nanotube-based field-emitters over the past two decades, and they have been investigated for devices ranging from flat-panel displays to vacuum tubes and electron microscopes. Other electron emission mechanisms from carbon nanotubes, such as photoemission, secondary emission, and thermionic emission, have also been studied, although to a lesser degree than field-emission. This paper presents an overview of the topic, with emphasis on these less-explored mechanisms, although field-emission is also discussed. We will see that not only is electron emission from nanotubes promising for electron-source applications, but also its study could reveal unusual phenomena and open the door to new devices that are not directly related to electron beams.

Field Emission and Electrical Switching Properties of Large-Area CuTCNQ Nanotube Arrays

2010 ◽  
Vol 10 (1) ◽  
pp. 237-243 ◽  
Author(s):  
Huibiao Liu ◽  
Zheng Liu ◽  
Xuemin Qian ◽  
Yanbing Guo ◽  
Shuang Cui ◽  
...  
Keyword(s):  
Field Emission ◽  
Nanotube Arrays ◽  
Large Area ◽  
Electrical Switching

Current limitation in large-area self-aligned gated field emission arrays

2014 ◽  
Author(s):  
Arash A. Fomani ◽  
Michael E. Swanwick ◽  
Luis F. Velasquez-Garcia ◽  
Akintunde I. Akinwande
Keyword(s):  
Field Emission ◽  
Large Area ◽  
Current Limitation ◽  
Field Emission Arrays

scholarly journals Improved Field Emission Properties of Carbon Nanostructures by Laser Surface Engineering

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1931
Author(s):  
Minh Nhat Dang ◽  
Minh Dang Nguyen ◽  
Nguyen Khac Hiep ◽  
Phan Ngoc Hong ◽  
In Hyung Baek ◽  
...  
Keyword(s):  
Field Emission ◽  
Edge Effect ◽  
Carbon Nanostructures ◽  
Surface Engineering ◽  
Nanostructured Carbon ◽  
Carbon Cathode ◽  
Electron Sources ◽  
Field Emission Properties ◽  
Turn On ◽  
New Type

We herein present an alternative geometry of nanostructured carbon cathode capable of obtaining a low turn-on field, and both stable and high current densities. This cathode geometry consisted of a micro-hollow array on planar carbon nanostructures engineered by femtosecond laser. The micro-hollow geometry provides a larger edge area for achieving a lower turn-on field of 0.70 V/µm, a sustainable current of approximately 2 mA (about 112 mA/cm2) at an applied field of less than 2 V/µm. The electric field in the vicinity of the hollow array (rim edge) is enhanced due to the edge effect, that is key to improving field emission performance. The edge effect of the micro-hollow cathode is confirmed by numerical calculation. This new type of nanostructured carbon cathode geometry can be promisingly applied for high intensity and compact electron sources.

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