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 Researchers develop key power-splitting component for terahertz waves
30.06.2016 | Brown University

nachricht LAMA 2.0 accelerates more than just numerical applications
21.06.2016 | Fraunhofer-Institut für Algorithmen und Wissenschaftliches Rechnen SCAI

All articles from Information Technology >>>

The most recent press releases about innovation >>>

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

Im Focus: Thousands on one chip: New Method to study Proteins

Since the completion of the human genome an important goal has been to elucidate the function of the now known proteins: a new molecular method enables the investigation of the function for thousands of proteins in parallel. Applying this new method, an international team of researchers with leading participation of the Technical University of Munich (TUM) was able to identify hundreds of previously unknown interactions among proteins.

The human genome and those of most common crops have been decoded for many years. Soon it will be possible to sequence your personal genome for less than 1000...

Im Focus: Optical lenses, hardly larger than a human hair

3D printing enables the smalles complex micro-objectives

3D printing revolutionized the manufacturing of complex shapes in the last few years. Using additive depositing of materials, where individual dots or lines...

Im Focus: Flexible OLED applications arrive

R2D2, a joint project to analyze and development high-TRL processes and technologies for manufacture of flexible organic light-emitting diodes (OLEDs) funded by the German Federal Ministry of Education and Research (BMBF) has been successfully completed.

In contrast to point light sources like LEDs made of inorganic semiconductor crystals, organic light-emitting diodes (OLEDs) are light-emitting surfaces. Their...

Im Focus: Unexpected flexibility found in odorant molecules

High resolution rotational spectroscopy reveals an unprecedented number of conformations of an odorant molecule – a new world record!

In a recent publication in the journal Physical Chemistry Chemical Physics, researchers from the Max Planck Institute for the Structure and Dynamics of Matter...

Im Focus: 3-D printing produces cartilage from strands of bioink

Strands of cow cartilage substitute for ink in a 3D bioprinting process that may one day create cartilage patches for worn out joints, according to a team of engineers. "Our goal is to create tissue that can be used to replace large amounts of worn out tissue or design patches," said Ibrahim T. Ozbolat, associate professor of engineering science and mechanics. "Those who have osteoarthritis in their joints suffer a lot. We need a new alternative treatment for this."

Cartilage is a good tissue to target for scale-up bioprinting because it is made up of only one cell type and has no blood vessels within the tissue. It is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Quantum technologies to revolutionise 21st century - Nobel Laureates discuss at Lindau

30.06.2016 | Event News

International Conference ‘GEO BON’ Wants to Close Knowledge Gaps in Global Biodiversity

28.06.2016 | Event News

ERES 2016: The largest conference in the European real estate industry

09.06.2016 | Event News

 
Latest News

Modeling NAFLD with human pluripotent stem cell derived immature hepatocyte like cells

30.06.2016 | Health and Medicine

Rice University lab runs crowd-sourced competition to create 'big data' diagnostic tools

30.06.2016 | Life Sciences

A drop of water as a model for the interplay of adhesion and stiction

30.06.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>