Navigation Links
'Nanocrystal doping' developed by Hebrew University researchers enhances semiconductor nanocrystals

Jerusalem, April 3, 2011 -- 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.

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 prestigious 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.


Contact: Jerry Barach
The Hebrew University of Jerusalem

Related biology technology :

1. New imaging technique reveals the atomic structure of nanocrystals
2. Gold solution for enhancing nanocrystal electrical conductance
3. Strain on nanocrystals could yield colossal results
4. New nanocrystalline diamond probes overcome wear
5. Penn collaboration leads to simpler method for building varieties of nanocrystal superlattices
6. Breakthrough in nanocrystals growth
7. TU Delft identifies huge potential of nanocrystals in fuel cells
8. Single-step technique produces both p-type and n-type doping for future graphene devices
9. Doping graphene
10. Human Trial Results Show Plant Extract Tops Drug at Regulating Blood Sugar Levels; Huge Market Seen for Newly Developed Food Additive Emulin™
11. FDA Approves Clinical Studies of a Novel Anti-Cancer Drug Developed by Italian Researchers
Post Your Comments:
Related Image:
'Nanocrystal doping' developed by Hebrew University researchers enhances semiconductor nanocrystals
(Date:12/1/2015)... ... December 01, 2015 , ... Park Systems ... an add-on scanning ion conductance microscopy module to Park NX10 that is the ... , Park SICM benefits virtually all materials characterization that require measurements in liquid ...
(Date:12/1/2015)... SAN DIEGO , December 1, 2015 Dr. Harry Lander ... serving as Chief Science Officer and recruits ... Dr. Harry Lander , President of Regen, expands his role ... and recruits five distinguished scientists to ... of Regen, expands his role to include ...
(Date:11/30/2015)... ... November 30, 2015 , ... Global Stem Cells Group ... of a new closed system for isolating adipose-derived stem cells. The announcement starts a ... of adipose tissue. SVF is a component of the lipoaspirate obtained from liposuction of ...
(Date:11/30/2015)... 2015 Partnership includes an MPP ... for the u niversity , s ... treatment s cale - up through ... Africa , where licensees based anywhere in the world will have ... --> Africa , where licensees based anywhere in the world ...
Breaking Biology Technology:
(Date:11/9/2015)... 09, 2015 ... the "Global Law Enforcement Biometrics Market ... --> ) has announced the ... Biometrics Market 2015-2019" report to their ... ( ) has announced the addition ...
(Date:10/29/2015)... , Oct. 29, 2015   MedNet Solutions ... the entire spectrum of clinical research, is pleased to ... High Tech Association (MHTA) as one of only three ... the "Software – Small and Growing" category. The Tekne Awards ... who have shown superior technology innovation and leadership. ...
(Date:10/29/2015)... , Oct. 29, 2015  Connected health pioneer, ... the explosion of technology-enabled health and wellness, and the ... book, The Internet of Healthy Things ... or smartphones even existed, Dr. Kvedar, vice president, Connected ... health care delivery, moving care from the hospital or ...
Breaking Biology News(10 mins):