20. Recent developments in broad area field emission cold cathodes

ABSTRACTImaging of field emission and photoemission from diamond surfaces is accomplished with a high resolution photo-electron emission microscope (PEEM). Measurements obtained as a function of sample temperature up to 1000°C display thermionic field emission images (TFEEM). The system can also record the emission current versus applied voltage. N-doped diamond films have been produced by MPCVD with a N/C gas phase ratio of 48. The surfaces display uniform emission in PEEM at all temperatures. No FEEM images are detectable below 500°C. At ∼680°C the T-FEEM and PEEM images are nearly identical in intensity and uniformity. This is to be contrasted with other carbon based cold cathodes in which the emission is observed from only a low density of highly emitting sites. The I/V measurements obtained from the N-doped films in the T-FEEM configuration show a component that depends linearly on voltage at low fields. At higher fields, an approximately exponential dependence is observed. At low temperatures employed (<700°C), the results indicate a thermionic component to the emitted current.

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Industrial application of cold cathodes based on field emission in microwave devices

Abstracts. International Vacuum Electronics Conference 2000 (Cat. No.00EX392) ◽

10.1109/ove:ec.2000.847466 ◽

2002 ◽

Author(s):

V.I. Makhov

Keyword(s):

Field Emission ◽

Industrial Application ◽

Microwave Devices ◽

Cold Cathodes

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Numerical Analysis of Field Emission and Thermally Enhanced Emission from Broad‐Area Electrodes in Vacuum

Journal of Applied Physics ◽

10.1063/1.1658714 ◽

1970 ◽

Vol 41 (2) ◽

pp. 563-571 ◽

Cited By ~ 29

Author(s):

G. A. Farrall

Keyword(s):

Numerical Analysis ◽

Field Emission ◽

Broad Area

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Electron cold sources: Nanotechnology contribution to field emitters

10.1093/oxfordhb/9780199533060.013.21 ◽

2017 ◽

Author(s):

Vu Thien Binh

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanotube ◽

Field Emission ◽

Driving Forces ◽

Industrial Applications ◽

Single Atom ◽

Cold Cathodes ◽

Field Emitters ◽

Carbon Nanopearls ◽

Field Emission Cathodes

This article reviews recent advances in field emission cathodes and their applications, focusing on a number of possibilities emerging from the field of nanotechnology. It begins with an overview of the driving forces for the evolution of cold cathodes, laying emphasis on their fundamental characteristics and industrial applications as well as the bottlenecks of metallic field emitters. It then considers single-atom emitters, followed by different examples where the advent of nanotechnology has contributed towards improving new cold cathodes. It also discusses the Fresnel projection microscope and the microgun, a route to the microcolumn approach which is associated with the nanotip; a host of material issues for field emitters, taking into account carbon nanocompounds; carbon-nanotube field emitters; and carbon-nanopearl field emitters. The article concludes with an evaluation of the applications and uses of carbon nanocompounds, carbon nanotubes and carbon nanopearls as cold cathodes.

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