Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Computer simulations: Finding the right mix

28.03.2014

Computer simulations indicate that mixing silicon with other materials improves the diversity of nanoscale electronic devices

The semiconductor silicon lies at the heart of the current revolution in electronics and computing. In particular, it can produce compact integrated circuits when processed by modern techniques capable of fabricating structures just a few nanometers in size.


Cross-sectional view of stable nanowires made from carbon–silicon (left), germanium–silicon (center) and tin–silicon (right), as predicted by calculations. The silicon atoms (yellow) are found at the edge of the nanowire when alloyed with tin (gray) and germanium (green). In contrast, in carbon–silicon nanowires (where carbon is indicated in black), they have an ordered arrangement.

© 2014 A*STAR Institute of High Performance Computing

The semiconductor silicon lies at the heart of the current revolution in electronics and computing. In particular, it can produce compact integrated circuits when processed by modern techniques capable of fabricating structures just a few nanometers in size.

Now, Man-Fai Ng and Teck Leong Tan at the A*STAR Institute of High Performance Computing in Singapore have shown that mixing silicon with similar materials can open the door to the fabrication of nanoscale devices with a diverse array of properties that have a wider range of applications1.

Now, Man-Fai Ng and Teck Leong Tan at the A*STAR Institute of High Performance Computing in Singapore have shown that mixing silicon with similar materials can open the door to the fabrication of nanoscale devices with a diverse array of properties that have a wider range of applications1.

Ng and Tan used state-of-the-art computer simulations to assess the structural stability and electronic properties of silicon-based nanowires. As their name suggests, nanowires are just a few nanometers wide but can be up to a millimeter long. They exhibit unusual electronic properties because their small width confines the motion of electrons across the wire.

The properties of silicon nanowires are well established, but there is considerable scope to expand their applicability. Scientists anticipate they could realize a more diverse range of characteristics by partially replacing silicon with other elements that are in the same column as silicon in the periodic table. There are many potential materials — including carbon, germanium and tin — each of which can be combined with silicon in any ratio to form an alloy.

Consequently, the total number of possible alloys is immense. The researchers thus undertook a comprehensive search of all these silicon-based alloys to determine which are atomically stable and which have the best properties for nanowire devices.

Ng and Tan employed three mathematical techniques (namely, density functional theory, the cluster expansion method and the Monte Carlo method) to simulate different atomic arrangements in nanowires.

“Instead of evaluating all possible alloy structures, our multiscaled simulation approach enabled rapid large-scale comparison of different combinations of alloy structures and selected the thermodynamically stable ones,” explained Ng.

The most stable germanium–silicon and tin–silicon nanowires were found to be those in which the silicon atoms are concentrated around the edge of the wire and the other atomic species are at the core. Conversely, an optimum carbon–silicon nanowire exhibited an ordered arrangement of the atomic species (see image).

Once they had identified the optimum atomic arrangement, Ng and Tan calculated the energy bandgap — a critical parameter for determining the electronic properties of semiconductors. “Next, we plan to improve the bandgap prediction for silicon-based nanowires and develop our approach to address more complicated nanosystems for energy applications,” says Ng.

The A*STAR-affiliated researchers contributing to this research are from the Institute of High Performance Computing 

Associated links

Journal information

Ng, M.-F. & Tan, T. L. Unveiling stable group IV alloy nanowires via a comprehensive search and their electronic band characteristics. Nano Letters 13, 4951−4956 (2013).

A*STAR Research | ResearchSEA News
Further information:
http://www.researchsea.com

More articles from Information Technology:

nachricht A novel hybrid UAV that may change the way people operate drones
28.03.2017 | Science China Press

nachricht Timing a space laser with a NASA-style stopwatch
28.03.2017 | NASA/Goddard Space Flight Center

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>