Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Silicon superlattices: New waves in thermoelectricity

Max G. Lagally
Max G. Lagally

Abstract:
University of Wisconsin-Madison research team has developed a new method for using nanoscale silicon that could improve devices that convert thermal energy into electrical energy.

Silicon superlattices: New waves in thermoelectricity

Madison, WI | Posted on March 31st, 2009

The team, led by Erwin W. Mueller Professor and Bascom Professor of Surface Science Max Lagally, published its findings in the March 24 issue of the journal ACS Nano.

Thermoelectric devices can use electricity to cool, or conversely convert heat to electricity. To improve efficiency in tiny thermoelectric devices, researchers build superlattices of alternating thin layers of two different semiconductor materials, called heterojunctions. Charges in multi-layer heterojunction wires travel through a periodic electric field that influences their motion; however, it is difficult to create modulation large enough to be effective with traditional heterojunctions, Lagally says.

The UW-Madison team addressed the problem by creating a superlattice from a single material: a sheet of silicon nanometers thick, called a nanomembrane, and cutting it into ribbons nanometers wide. The researchers can induce localized strain in the silicon, creating an effective strain wave that causes charges the electric field in the ribbon to vary periodically.

"Essentially we're making the equivalent of a heterojunction superlattice with one material," says Lagally, whose home department is materials science and engineering. "We're actually doing better with these strained regions than you can do easily with multiple-chemical-component systems."

The strained-silicon superlattices display greater electric field modulation than their heterojunction counterparts, so they may improve silicon thermoelectrics near or above room temperature. In addition, they are relatively easy to manufacture. Lagally and his group theorize that their method could apply to any type of semiconductor nanomembrane.

"It's cool in several ways: It's a single material, the modulation in the electric field is bigger than what others can make easily, and it's very straightforward," says Lagally.

Co-authors of the paper include Lagally, UW-Madison postdoctoral associate Hing-Huang Huang, graduate students Clark Ritz and Bozidar Novakovic, assistant scientist Frank Flack, associate scientist Don Savage, Materials Science and Engineering Associate Professor Paul Evans, and Electrical and Computer Engineering Assistant Professor Irena Knezevic, along with Decai Yu, Yu Zhang and Professor Feng Liu of the University of Utah.

The U.S. Department of Energy, the National Science Foundation and the Air Force Office of Scientific Research supported this work.

####

For more information, please click here

Copyright © University of Wisconsin-Madison

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

Engineering a better 'Do: Purdue researchers are learning how August 4th, 2015

Proving nanoparticles in sunscreen products August 4th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanoparticles Give Antibacterial Properties to Machine-Woven Carpets August 4th, 2015

Possible Futures

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanozirconia Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Self-Healing Nano Anti-rust Coatings Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Nano Spray Instrument Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Announcements

Engineering a better 'Do: Purdue researchers are learning how August 4th, 2015

Proving nanoparticles in sunscreen products August 4th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanoparticles Give Antibacterial Properties to Machine-Woven Carpets August 4th, 2015

Energy

Transparent, electrically conductive network of encapsulated silver nanowires: A novel electrode for optoelectronics August 1st, 2015

Springer and Tsinghua University Press present the second Nano Research Award: Paul Alivisatos of the University of California Berkeley receives the honor for outstanding contributions in nanoscience July 30th, 2015

Controlling Dynamic Behavior of Carbon Nanosheets in Structures Made Possible July 30th, 2015

March 2016; 6th Int'l Conference on Nanostructures in Iran July 29th, 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