Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Nanotubes act as 'thermal velcro'

Nanotubes act as 'thermal velcro' to reduce computer-chip heating

West Lafayette, IN | Posted on May 01, 2006

Engineers have created carpets made of tiny cylinders called carbon nanotubes to enhance the flow of heat at a critical point where computer chips connect to cooling devices called heat sinks, promising to help keep future chips from overheating.

Researchers are trying to develop new types of "thermal interface materials" that conduct heat more efficiently than conventional materials, improving overall performance and helping to meet cooling needs of future chips that will produce more heat than current microprocessors. The materials, which are sandwiched between silicon chips and the metal heat sinks, fill gaps and irregularities between the chip and metal surfaces to enhance heat flow between the two.

Purdue University researchers have made several new thermal interface materials with carbon nanotubes, including a Velcro-like nanocarpet. "The bottom line is the performance that we see with nanotubes is significantly better than comparable state-of-the-art commercial materials," said Timothy Fisher, an associate professor of mechanical engineering who is leading the research. "Carbon nanotubes have excellent heat-conduction properties, and our ability to fabricate them in a controlled manner has been instrumental in realizing this application."

Recent findings have shown that the nanotube-based interfaces can conduct several times more heat than conventional thermal interface materials at the same temperatures. The nanocarpet, called a "carbon nanotube array thermal interface," can be attached to both the chip and heat sink surfaces.

"We say it's like Velcro because it creates an interwoven mesh of fibers when both sides of the interface are coated with nanotubes," Fisher said. "We don't mean that it creates a strong mechanical bond, but the two pieces come together in such a way that they facilitate heat flow, becoming the thermal equivalent of Velcro. In some cases, using a combination of nanotube material and traditional interface materials also shows a strong synergistic effect."

Findings related to the combination of carbon nanotubes and traditional interface materials are detailed in a paper appearing in the May issue of the International Journal of Heat and Mass Transfer. The paper was written by mechanical engineering doctoral student Jun Xu and Fisher.

Heat is generated at various points within the intricate circuitry of computer chips and at locations where chips connect to other parts. As heat flows through conventional thermal interface materials, the temperature rises about 15 degrees Celsius, whereas the nanotube array material causes a rise of about 5 degrees or less.

It will be necessary to find more efficient thermal interface materials in the future because as computer chips become increasingly more compact, more circuitry will be patterned onto a smaller area, producing additional heat. Excess heat reduces the performance of computer chips and can ultimately destroy the delicate circuits.

The nanotubes range in diameter from less than one nanometer to about 100 nanometers. A nanometer is a billionth of a meter, or about the distance of 10 atoms strung together.

The nanotube carpets also might have military and other commercial applications for cooling "power electronics," which are systems that control and convert the flow of electrical power so that it can be used for various purposes on an aircraft, ship or vehicle.

The research has been funded by Purdue's Cooling Technologies Research Center, supported by the National Science Foundation, industry and Purdue to help corporations develop miniature cooling technologies for a wide range of applications, from electronics and computers to telecommunications and advanced aircraft. Applications in power electronics are being supported by the Air Force Research Laboratory in association with the Birck Nanotechnology Center at Purdue's Discovery Park.

The technology is ready for commercialization and is being pursued by several corporate members of the cooling research center, including Nanoconduction Inc., a startup company in Sunnyvale, Calif., which is a new member of the cooling center.

####


Writer: Emil Venere, (765) 494-4709, venere@purdue.edu

Source Timothy Fisher, (765) 494-5627, tsfisher@purdue.edu

Related Web site:
Timothy Fisher: tools.ecn.purdue.edu/ME/Fac_Staff/fisher.whtml

Note to Journalists: An electronic copy of the research paper is available from Emil Venere, (765) 494-4709, venere@purdue.edu

ABSTRACT
Enhancement of thermal interface materials with carbon

Jun Xu, Timothy S. Fisher

This paper describes an experimental study of thermal contact conductance enhancement enabled by carbon nanotube (CNT) arrays synthesized directly on silicon wafers using plasma-enhanced chemical vapor deposition. Testing based on the one-dimensional reference bar method occurred in a high-vacuum environment with radiation shielding, and temperature measurements were made with an infrared camera. Results from other thermal interface materials are presented, as well as combinations of these materials with CNT arrays. Dry CNT arrays produce a minimum thermal interface resistance of 19.8 mm2 K/ W, while the combination of a CNT array and a phase change material produces a minimum resistance of 5.2 mm2 K/W.Text of abstract, with leading set at 14 points, so it doesn't take as much room.

Contact:
Purdue University
News Service
400 Centennial Mall Drive, Rm. 324
West Lafayette, IN 47907-2016
(765) 494-2096
fax: (765) 494-0401
purduenews@purdue.edu

Copyright © Purdue University

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

Possible Futures

Silk bio-ink could help advance tissue engineering with 3-D printers September 2nd, 2015

Sediment dwelling creatures at risk from nanoparticles in common household products August 13th, 2015

Harris & Harris Group Reports Financial Statements as of June 30, 2015, and Announces a Stock Repurchase Program August 10th, 2015

Molecular trick alters rules of attraction for non-magnetic metals August 5th, 2015

Chip Technology

For 2-D boron, it's all about that base: Rice University theorists show flat boron form would depend on metal substrates September 2nd, 2015

Phagraphene, a 'relative' of graphene, discovered September 2nd, 2015

Nanometrics to Participate in the Citi 2015 Global Technology Conference August 26th, 2015

Kwansei Gakuin University in Hyogo, Japan, uses Raman microscopy to study crystallographic defects in silicon carbide wafers August 25th, 2015

Nanotubes/Buckyballs/Fullerenes

For 2-D boron, it's all about that base: Rice University theorists show flat boron form would depend on metal substrates September 2nd, 2015

$200K Awarded to Develop In Vitro Lung Test for Toxicity of Inhaled Nanomaterials: In Vitro Lung Test Designed to Protect Human Health and Replace Animal Testing September 1st, 2015

Developing Component Scale Composites Using Nanocarbons August 26th, 2015

Southampton scientists find new way to detect ortho-para conversion in water August 25th, 2015

Nanoelectronics

Turning clothing into information displays September 2nd, 2015

Phagraphene, a 'relative' of graphene, discovered September 2nd, 2015

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

'Quantum dot' technology may help light the future August 19th, 2015

Announcements

For 2-D boron, it's all about that base: Rice University theorists show flat boron form would depend on metal substrates September 2nd, 2015

Silk bio-ink could help advance tissue engineering with 3-D printers September 2nd, 2015

Phagraphene, a 'relative' of graphene, discovered September 2nd, 2015

A marine creature's magic trick explained: Crystal structures on the sea sapphire's back appear differently depending on the angle of reflection September 2nd, 2015

Military

Seeing quantum motion August 30th, 2015

These microscopic fish are 3-D-printed to do more than swim: Researchers demonstrate a novel method to build microscopic robots with complex shapes and functionalities August 26th, 2015

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

Industrial Nanotech, Inc. Provides Update On Hospital Project, PCAOB Audit, and New Heat Shield™ Line August 24th, 2015

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







Car Brands
Buy website traffic