Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > New player in electron field emitter technology makes for better imaging and communications

NIST's silicon carbide field emitter produces a flow of electrons comparable to hot sources, but without the need for heat. By dissolving much of the material away to make a porous structure with a large surface area, NIST scientists ensured that as an electron emission point on an individual spike wears out, another is available to take its place, making the array more durable as a whole.

Credit: Sharifi/NIST
NIST's silicon carbide field emitter produces a flow of electrons comparable to hot sources, but without the need for heat. By dissolving much of the material away to make a porous structure with a large surface area, NIST scientists ensured that as an electron emission point on an individual spike wears out, another is available to take its place, making the array more durable as a whole.

Credit: Sharifi/NIST

Abstract:
Scientists at the National Institute of Standards and Technology (NIST) and the University of Maryland, College Park, have built a practical, high-efficiency nanostructured electron source. Described in the journal Nanotechnology*, this new, patent-pending technology could lead to improved microwave communications and radar, and more notably to new and improved X-ray imaging systems for security and health-care applications.

New player in electron field emitter technology makes for better imaging and communications

Gaithersburg, MD | Posted on March 9th, 2013

While thermionic electron sources such as the hot filaments inside cathode ray tubes have largely been replaced by LEDs and liquid crystals for display screens and televisions, they are still used to produce microwaves for radar and X-rays for medical imaging. Thermionic sources use an electric current to boil electrons off the surface of a wire filament, similar to the way an incandescent light bulb uses an electric current to heat a wire filament until it glows.

And like an incandescent light bulb, thermionic sources are generally not very energy efficient. It takes a lot of power to boil off the electrons, which spew in every direction. Those that aren't lost have to be captured and focused using a complicated system of electric and magnetic fields. Field emission electron sources require much less power and produce a much more directional and easily controllable stream of electrons.

To build their field emission source, the NIST team took a tough material—silicon carbide—and used a room-temperature chemical process to make it highly porous like a sponge. They then patterned it into microscopic emitting structures in the shape of pointed rods or sharp-edged fins. When an electric field is applied, these novel field emitters can produce an electron flow comparable to a thermionic source but without all the disadvantages—and with many advantages.

According to co-inventor Fred Sharifi, the new field emitters have inherently fast response times compared with thermionic sources, and the absence of heat makes it easier to create arrays of sources. Moreover, the porous nanostructure of the emitters makes them very reliable. Even if the emitter surface wears away during use—a common problem—the newly exposed material continues to work just as well.

Sharifi says that the NIST field emitters hold the potential to enhance the resolution and quality of X-ray images and allow for new modes of detection.

"X-ray images are based on the density of the material being examined, which limits their ability to see certain types of materials, including some types of explosives," says Sharifi. "Our field emitter will let us see not just that something is there, but, because we can build large arrays and place them at different angles, we can identify the material in question by looking at how the X-rays coming from different directions scatter from the object."

The technology is available for licensing through NIST's Technology Partnerships Office.

*M. Kang, H. Lezec and F. Sharifi. Stable field emission from nanoporous silicon carbide. Nanotechnology. 24 (2013) 065201.

####

For more information, please click here

Contacts:
Mark Esser

301-975-8735

Copyright © National Institute of Standards and Technology (NIST)

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

National Conference on Nanomaterials, (NCN-2017) April 21st, 2017

NanoMONITOR shares its latest developments concerning the NanoMONITOR Software and the Monitoring stations April 21st, 2017

Nanomechanics, Inc. Unveils New Product at ICMCTF Show April 25th: Nanoindentation experts will launch the new Gemini that measures the interaction of two objects that are sliding across each other – not merely making contact April 21st, 2017

Imaging

Nanoparticles open new window for biological imaging: “Quantum dots” that emit infrared light enable highly detailed images of internal body structures April 10th, 2017

The Catholic University of Rome uses the JPK NanoWizard® AFM & CellHesion® systems to understand how cells sense and respond to mechanical stimuli April 5th, 2017

Tiny sensor lays groundwork for precision X-rays detection via endoscopy:Nanoscale fiber-integrated X-ray sensor opens new doors for medical imaging and radiotherapy March 29th, 2017

“Cysteine Rose” Wins 2016 Thermo Fisher Scientific Electron Microscopy Image Contest: Thermo Fisher honors Andrea Jacassi of the Italian Institute of Technology for image of cysteine crystals using focused ion beam techniques March 27th, 2017

Laboratories

NIST physicists show ion pairs perform enhanced 'spooky action' March 30th, 2017

A big leap toward tinier lines: Self-assembly technique could lead to long-awaited, simple method for making smaller microchip patterns March 27th, 2017

Govt.-Legislation/Regulation/Funding/Policy

NanoMONITOR shares its latest developments concerning the NanoMONITOR Software and the Monitoring stations April 21st, 2017

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Nano-SPEARs gently measure electrical signals in small animals: Rice University's tiny needles simplify data gathering to probe diseases, test drugs April 17th, 2017

Emergency Use Authorization for Gene-RADAR® Zika Virus Test: FDA Authorization for the Gene-RADAR® Zika Virus Test on the XPRIZE-Winning Gene-RADAR® Platform April 14th, 2017

Discoveries

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

Wood filter removes toxic dye from water April 21st, 2017

Rice crew revved for Nanocar Race: Nanocar creator James Tour and team take on international competition with single-molecule marvel April 20th, 2017

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Announcements

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

National Conference on Nanomaterials, (NCN-2017) April 21st, 2017

NanoMONITOR shares its latest developments concerning the NanoMONITOR Software and the Monitoring stations April 21st, 2017

Nanomechanics, Inc. Unveils New Product at ICMCTF Show April 25th: Nanoindentation experts will launch the new Gemini that measures the interaction of two objects that are sliding across each other – not merely making contact April 21st, 2017

Patents/IP/Tech Transfer/Licensing

Forge Nano 2017: 1st Quarter Media Update April 20th, 2017

Making Batteries From Waste Glass Bottles: UCR researchers are turning glass bottles into high performance lithium-ion batteries for electric vehicles and personal electronics April 19th, 2017

'Neuron-reading' nanowires could accelerate development of drugs for neurological diseases April 12th, 2017

Laser activated gold pyramids could deliver drugs, DNA into cells without harm: Microstructures create temporary pores in cells March 27th, 2017

Research partnerships

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Shedding light on the absorption of light by titanium dioxide April 14th, 2017

AIM Photonics Presents Cutting-Edge Integrated Photonics Technology Developments to Packed House at OFC 2017, the Optical Networking and Communication Conference & Exhibition April 11th, 2017

Nanoparticles open new window for biological imaging: “Quantum dots” that emit infrared light enable highly detailed images of internal body structures April 10th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project