Featured Research

from universities, journals, and other organizations

‘Nanocrystal doping’ results in semiconductor nanocrystals with enhanced electrical function

Date:
July 1, 2011
Source:
The Hebrew University of Jerusalem
Summary:
Researchers have achieved a breakthrough in the field of nanoscience by successfully altering nanocrystal properties with impurity atoms -- a process called doping -- thereby opening the way for the manufacture of improved semiconductor nanocrystals.

This is professor Uri Banin of the Center for Nanoscience and Nanotechnology at the Hebrew University of Jerusalem.
Credit: Hebrew University photo

Researchers at the Hebrew University of Jerusalem have achieved a breakthrough in the field of nanoscience by successfully altering nanocrystal properties with impurity atoms -- a process called doping -- thereby opening the way for the manufacture of improved semiconductor nanocrystals.

Related Articles


Semiconductor nanocrystals consist of tens to thousands of atoms and are 10,000 times smaller than the width of a human hair. These tiny particles have uses in a host of fields, such as solid-state lighting, solar cells and bio-imaging. One of the main potential applications of these remarkable materials is in the semiconductor industry, where intensive miniaturization has been taking place for the last 50 years and is now in the nanometer range.

However, these semiconductors are poor electrical conductors, and in order to use them in electronic circuits, their conductivity must be tuned by the addition of impurities. In this process, foreign atoms, called impurities, are introduced into the semiconductor, causing an improvement in its electrical conductivity.

Today, the semiconductor industry annually spends billions of dollars in efforts to intentionally add impurities into semiconductor products, which is a major step in the manufacturing of numerous electronic products, including computer chips, light emitting diodes and solar cells.

Due to the importance of doping to the semiconductor industry, researchers worldwide have made continuing attempts at doping nanocrystals in order to achieve ever greater miniaturization and to improve production methods for electronic devices. Unfortunately, these tiny crystals are resistant to doping, as their small size causes the impurities to be expelled. An additional problem is the lack of analytical techniques available to study small amounts of dopants in nanocrystals. Due to this limitation, most of the research in this area has focused on introducing magnetic impurities, which can be analyzed more easily. However, the magnetic impurities don't really improve the conductivity of the nanocrystal.

Prof. Uri Banin and his graduate student, David Mocatta, of the Hebrew University Center for Nanoscience and Nanotechnology, have achieved a breakthrough in their development of a straightforward, room- temperature chemical reaction to introduce impurity atoms of metals into the semiconductor nanocrystals. They saw new effects not previously reported. However, when the researchers tried to explain the results, they found that the physics of doped nanocrystals was not very well understood.

Bit by bit, in collaboration with Prof. Oded Millo of the Hebrew University and with Guy Cohen and Prof. Eran Rabani of Tel Aviv University, they built up a comprehensive picture of how the impurities affect the properties of nanocrystals. The initial difficulty in explaining this process proved to be a great opportunity, as they discovered that the impurity affects the nanocrystal in unexpected ways, resulting in new and intriguing physics.

"We had to use a combination of many techniques that when taken together make it obvious that we managed to dope the nanocrystals. It took five years but we got there in the end," said Mocatta.

This breakthrough was reported recently in the journal Science. It sets the stage for the development of many potential applications with nanocrystals, ranging from electronics to optics, from sensing to alternative energy solutions. Doped nanocrystals can be used to make new types of nanolasers, solar cells, sensors and transistors, meeting the exacting demands of the semiconductor industry.


Story Source:

The above story is based on materials provided by The Hebrew University of Jerusalem. Note: Materials may be edited for content and length.


Journal Reference:

  1. D. Mocatta, G. Cohen, J. Schattner, O. Millo, E. Rabani, U. Banin. Heavily Doped Semiconductor Nanocrystal Quantum Dots. Science, 2011; 332 (6025): 77 DOI: 10.1126/science.1196321

Cite This Page:

The Hebrew University of Jerusalem. "‘Nanocrystal doping’ results in semiconductor nanocrystals with enhanced electrical function." ScienceDaily. ScienceDaily, 1 July 2011. <www.sciencedaily.com/releases/2011/04/110404110415.htm>.
The Hebrew University of Jerusalem. (2011, July 1). ‘Nanocrystal doping’ results in semiconductor nanocrystals with enhanced electrical function. ScienceDaily. Retrieved January 27, 2015 from www.sciencedaily.com/releases/2011/04/110404110415.htm
The Hebrew University of Jerusalem. "‘Nanocrystal doping’ results in semiconductor nanocrystals with enhanced electrical function." ScienceDaily. www.sciencedaily.com/releases/2011/04/110404110415.htm (accessed January 27, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Tuesday, January 27, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cablevision Enters Wi-Fi Phone Fray

Cablevision Enters Wi-Fi Phone Fray

Reuters - Business Video Online (Jan. 26, 2015) The entry by Cablevision and Google could intensify the already heated price wars for mobile phone service. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Hector the Robot Mimics a Giant Stick Insect

Hector the Robot Mimics a Giant Stick Insect

Reuters - Innovations Video Online (Jan. 26, 2015) A robot based on a stick insect can navigate difficult terrain autonomously and adapt to its surroundings. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Raw: Pilot Uses Full-Plane Parachute in Crash

Raw: Pilot Uses Full-Plane Parachute in Crash

AP (Jan. 26, 2015) A pilot en route to Hawaii crashed his single-engine plane into the Pacific Ocean Monday and escaped safely thanks to the use of a full-plane parachute. US Coast Guard video captures the dramatic landing. (Jan. 26) Video provided by AP
Powered by NewsLook.com
Scientists Model Flying, Walking Drone After Vampire Bats

Scientists Model Flying, Walking Drone After Vampire Bats

Buzz60 (Jan. 26, 2015) Swiss scientists build a new drone that can both fly and walk, modeling it after the movements of common vampire bats. Jen Markham (@jenmarkham) has the story. 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