Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

One Direction: Researchers Grow Nanocircuitry with Semiconducting Graphene Nanoribbons

16.10.2015

In a development that could revolutionize electronic ciruitry, a research team from the University of Wisconsin at Madison (UW) and the U.S. Department of Energy’s Argonne National Laboratory has confirmed a new way to control the growth paths of graphene nanoribbons on the surface of a germainum crystal.

Germanium is a semiconductor and this method provides a straightforward way to make semiconducting nanoscale circuits from graphene, a form of carbon only one atom thick.


Gusinger et. al

Researchers at Argonne’s Center for Nanoscale Materials have confirmed the growth of self-directed graphene nanoribbons on the surface of the semiconducting material germanium by researchers at the University of Wisconsin at Madison.

The method was discovered by UW scientists and confirmed in tests at Argonne.

“Some researchers have wanted to make transistors out of carbon nanotubes but the problem is that they grow in all sorts of directions,” said Brian Kiraly of Argonne. “The innovation here is that you can grow these along circuit paths that works for your tech.”

UW researchers used chemical vapor deposition to grow graphene nanoribbons on germanium crystals. This technique flows a mixture of methane, hydrogen and argon gases into a tube furnace. At high temperatures, methane decomposes into carbon atoms that settle onto the germanium's surface to form a uniform graphene sheet. By adjusting the chamber's settings, the UW team was able to exert very precise control over the material.

"What we've discovered is that when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges," said Michael Arnold, an associate professor of materials science and engineering at UW-Madison. "The widths can be very, very narrow and the lengths of the ribbons can be very long, so all the desirable features we want in graphene nanoribbons are happening automatically with this technique."

Graphene, a one-atom-thick, two-dimensional sheet of carbon atoms, is known for moving electrons at lightning speed across its surface without interference. This high mobility makes the material an ideal candidate for faster, more energy-efficient electronics.

However, the semiconductor industry wants to make circuits start and stop electrons at will via band-gaps, as they do in computer chips. As a semimetal, graphene naturally has no band-gaps, making it a challenge for widespread industry adoption. Until now.

To confirm these findings, UW researchers went to Argonne staff scientists Brian Kiraly and Nathan Guisinger at the Center for Nanoscale Materials, a DOE Office of Science User Facility located at Argonne.

“We have some very unique capabilities here at the Center for Nanoscale Materials,” said Guisinger. “Not only are our facilities designed to work with all different sorts of materials from metals to oxides, we can also characterize, grow and synthesize materials."

Using scanning tunneling microscopy, a technique using electrons (instead of light or the eyes) to see the characteristics of a sample, researchers confirmed the presence of graphene nanoribbons growing on the germanium. Data gathered from the electron signatures allowed the researchers to create images of the material’s dimensions and orientation. In addition, they were able to determine its band structure and extent to which electrons scattered throughout the material.

“We’re looking at fundamental physical properties to verify that it is, in fact, graphene and it shows some characteristic electronic properties,” said Kiraly. “What’s even more interesting is that these nanoribbons can be made to grow in certain directions on one side of the germanium crystal, but not the other two sides.”

For use in electronic devices, the semiconductor industry is primarily interested in three faces of a germanium crystal. Depicting these faces in terms of coordinates (X,Y,Z), where single atoms connect to each other in a diamond-like grid structure, each face of a crystal (1,1,1) will have axes that differ from one (1,1,0) to the other (1,0,0).

Previous research shows that graphene sheets can grow on germanium crystal faces (1,1,1) and (1,1,0). However, this is the first time any study has recorded the growth of graphene nanoribbons on the (1,0,0) face.

As their investigations continue, researchers can now focus their efforts on exactly why self-directed graphene nanoribbons grow on the (1,0,0) face and determine if there is any unique interaction between the germanium and graphene that may play a role.

This research is detailed in the paper "Direct oriented growth of armchair graphene nanoribbons on germanium," published in Nature Communications. The method for this work was led by Michael Arnold’s Advanced Materials for Energy and Electronics Group at UW-Madison. Confirmation of findings was led by Nathan Guisinger and Brian Kiraly at the Center for Nanoscale Materials at Argonne National Laboratory. Additional co-authors include Robert M. Jacobberger, Matthieu Fortin-Deschenes, Pierre L. Levesque, Kyle M. McElhinny, Gerald J. Brady, Richard Rojas Delgado, Susmit Singha Roy, Andrew Mannix, Max G. Lagally, Paul G. Evans, Patrick Desjardins, Richard Martel and Mark C. Hersam.

This work was supported in part by the U.S. Department of Energy’s (DOE) Office of Science, the Natural Science and Engineering Research Council, the University of Wisconsin Materials Research Science and Engineering Center, the Department of Defense (DOD) Air Force Office of Scientific Research and the National Science Foundation’s Graduate Research Fellowships.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit www.science.energy.gov

Contact Information
Justin Breaux
External Communications Specialist
jbreaux@anl.gov
Phone: 630-252-5823
Mobile: 312-342-9155

Justin Breaux | newswise
Further information:
http://www.anl.gov

More articles from Materials Sciences:

nachricht Physics, photosynthesis and solar cells
01.12.2016 | University of California - Riverside

nachricht New process produces hydrogen at much lower temperature
01.12.2016 | Waseda University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>