Featured Research

from universities, journals, and other organizations

Technique Tethers Molecules To Silicon With Atomic Precision

Date:
April 12, 2000
Source:
University Of Illinois At Urbana-Champaign
Summary:
Researchers at the University of Illinois have successfully tethered individual organic molecules at specific locations on silicon surfaces. The precise manipulation of molecules on the atomic scale is an important step in the potential merger of molecular electronics and silicon-based technology.

CHAMPAIGN, Ill. -- Researchers at the University of Illinois have successfully tethered individual organic molecules at specific locations on silicon surfaces. The precise manipulation of molecules on the atomic scale is an important step in the potential merger of molecular electronics and silicon-based technology.

Related Articles


"The semiconductor industry is fast approaching a fundamental limit on how many components can be crammed onto a conventional chip," said Joseph Lyding, a UI professor of electrical and computer engineering and a researcher at the university's Beckman Institute for Advanced Science and Technology. "We are exploring what we can make at the atomic level, and how we might merge that with what we perceive as end-of-the-road silicon technology."

To selectively bind molecules to a silicon surface, Lyding and graduate students Mark Hersam and Nathan Guisinger first passivate the silicon bonds with hydrogen. Then they use an ultra-high vacuum scanning tunneling microscope to break individual silicon-hydrogen bonds and dislodge hydrogen atoms from selected sites.

"We take advantage of the difference in chemical reactivity between clean silicon and hydrogen-passivated silicon," Hersam said. "By removing individual hydrogen atoms, we create holes in the clean silicon surface. Since these holes -- or dangling bonds -- serve as effective binding sites, molecules injected in the gas phase will spontaneously self-assemble into the predefined patterns."

A technique called feedback-controlled lithography gives the patterning process an atomic precision. "Feedback-controlled lithography works by actively monitoring the microscope feedback signal and the tunneling current during patterning, and immediately terminating the patterning process when a bond is broken," Lyding said. "By operating the microscope under feedback control, a carefully controlled dose of electrons can be written along a line or over an area to locally depassivate the surface and create templates of individual dangling bonds."

The researchers demonstrated the feasibility of their technique with three organic molecules: norbornadiene, copper phthalocyanine and carbon-60 "buckyballs." One advantage of organic molecules is that their end groups can be functionalized for potential electronic or mechanical switching properties.

"Now the fun can begin as we attempt to take advantage of what chemists can make to add functionality in the form of data storage or processing," Lyding said. "It may be possible to make molecular devices and switching elements that operate at a hundred trillion times a second."

While the technology for economically tethering billions of molecular devices on a chip surface does not yet exist, "we can make small numbers of the devices and test their function," Hersam said. "This is an important step in bridging the gap between molecular electronics and silicon technology."


Story Source:

The above story is based on materials provided by University Of Illinois At Urbana-Champaign. Note: Materials may be edited for content and length.


Cite This Page:

University Of Illinois At Urbana-Champaign. "Technique Tethers Molecules To Silicon With Atomic Precision." ScienceDaily. ScienceDaily, 12 April 2000. <www.sciencedaily.com/releases/2000/04/000406092018.htm>.
University Of Illinois At Urbana-Champaign. (2000, April 12). Technique Tethers Molecules To Silicon With Atomic Precision. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/2000/04/000406092018.htm
University Of Illinois At Urbana-Champaign. "Technique Tethers Molecules To Silicon With Atomic Precision." ScienceDaily. www.sciencedaily.com/releases/2000/04/000406092018.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

AFP (Nov. 21, 2014) Toyota presented its hydrogen fuel-cell compact car called "Mirai" to US consumers at the Los Angeles auto show. The car should go on sale in 2015 for around $60.000. It combines stored hydrogen with oxygen to generate its own power. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Google Announces Improvements To Balloon-Borne Wi-Fi Project

Google Announces Improvements To Balloon-Borne Wi-Fi Project

Newsy (Nov. 21, 2014) In a blog post, Google said its balloons have traveled 3 million kilometers since the start of Project Loon. Video provided by Newsy
Powered by NewsLook.com
Raw: Paralyzed Marine Walks With Robotic Braces

Raw: Paralyzed Marine Walks With Robotic Braces

AP (Nov. 21, 2014) Marine Corps officials say a special operations officer left paralyzed by a sniper's bullet in Afghanistan walked using robotic leg braces in a ceremony to award him a Bronze Star. (Nov. 21) Video provided by AP
Powered by NewsLook.com
British 'Bio-Bus' Is Powered By Human Waste

British 'Bio-Bus' Is Powered By Human Waste

Buzz60 (Nov. 21, 2014) British company GENeco debuted what its calling the Bio-Bus, a bus fueled entirely by biomethane gas produced from food scraps and sewage. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins