Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Discovery in growing graphene nanoribbons could enable faster, more efficient electronics

Progressively zoomed-in images of graphene nanoribbons grown on germanium. The ribbons automatically align perpendicularly and naturally grow in what is known as the armchair edge configuration.

Images: Arnold Research Group and Guisinger Research Group
Progressively zoomed-in images of graphene nanoribbons grown on germanium. The ribbons automatically align perpendicularly and naturally grow in what is known as the armchair edge configuration.

Images: Arnold Research Group and Guisinger Research Group

Abstract:
Graphene, an atom-thick material with extraordinary properties, is a promising candidate for the next generation of dramatically faster, more energy-efficient electronics. However, scientists have struggled to fabricate the material into ultra-narrow strips, called nanoribbons, that could enable the use of graphene in high-performance semiconductor electronics.

Discovery in growing graphene nanoribbons could enable faster, more efficient electronics

Madison, WI | Posted on August 11th, 2015

Now, University of Wisconsin-Madison engineers have discovered a way to grow graphene nanoribbons with desirable semiconducting properties directly on a conventional germanium semiconductor wafer. This advance could allow manufacturers to easily use graphene nanoribbons in hybrid integrated circuits, which promise to significantly boost the performance of next-generation electronic devices. The technology could also have specific uses in industrial and military applications, such as sensors that detect specific chemical and biological species and photonic devices that manipulate light.

In a paper published Aug. 10 in the journal Nature Communications, Michael Arnold, an associate professor of materials science and engineering at UW-Madison, Ph.D. student Robert Jacobberger, and their collaborators describe their new approach to producing graphene nanoribbons. Importantly, their technique can easily be scaled for mass production and is compatible with the prevailing infrastructure used in semiconductor processing.

"Graphene nanoribbons that can be grown directly on the surface of a semiconductor like germanium are more compatible with planar processing that's used in the semiconductor industry, and so there would be less of a barrier to integrating these really excellent materials into electronics in the future," Arnold says.

Graphene, a sheet of carbon atoms that is only one atom in thickness, conducts electricity and dissipates heat much more efficiently than silicon, the material most commonly found in today's computer chips. But to exploit graphene's remarkable electronic properties in semiconductor applications where current must be switched on and off, graphene nanoribbons need to be less than 10 nanometers wide, which is phenomenally narrow. In addition, the nanoribbons must have smooth, well-defined "armchair" edges in which the carbon-carbon bonds are parallel to the length of the ribbon.

Researchers have typically fabricated nanoribbons by using lithographic techniques to cut larger sheets of graphene into ribbons. However, this "top-down" fabrication approach lacks precision and produces nanoribbons with very rough edges.

Another strategy for making nanoribbons is to use a "bottom-up" approach such as surface-assisted organic synthesis, where molecular precursors react on a surface to polymerize nanoribbons. Arnold says surface-assisted synthesis can produce beautiful nanoribbons with precise, smooth edges, but this method only works on metal substrates and the resulting nanoribbons are thus far too short for use in electronics.

To overcome these hurdles, the UW-Madison researchers pioneered a bottom-up technique in which they grow ultra-narrow nanoribbons with smooth, straight edges directly on germanium wafers using a process called chemical vapor deposition. In this process, the researchers start with methane, which adsorbs to the germanium surface and decomposes to form various hydrocarbons. These hydrocarbons react with each other on the surface, where they form graphene.

Arnold's team made its discovery when it explored dramatically slowing the growth rate of the graphene crystals by decreasing the amount of methane in the chemical vapor deposition chamber. They found that at a very slow growth rate, the graphene crystals naturally grow into long nanoribbons on a specific crystal facet of germanium. By simply controlling the growth rate and growth time, the researchers can easily tune the nanoribbon width be to less than 10 nanometers.

"What we've discovered is that when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges," Arnold says. "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."

The nanoribbons produced with this technique start nucleating, or growing, at seemingly random spots on the germanium and are oriented in two different directions on the surface. Arnold says the team's future work will include controlling where the ribbons start growing and aligning them all in the same direction.

The researchers are patenting their technology through the Wisconsin Alumni Research Foundation. The research was primarily supported by the Department of Energy's Basic Energy Sciences program.

###

The Arnold group worked closely with various collaborators, including Nathan Guisinger at Argonne National Laboratory, Mark C. Hersam of Northwestern University, Richard Martel of the University of Montreal, and Patrick Desjardins of Polytechnique Montreal in addition to the research groups of Paul Evans and Max Lagally in the UW-Madison Department of Materials Science and Engineering, each of whom conducted important studies to determine the structure of the nanoribbons.

—Adam Malecek,

####

For more information, please click here

Contacts:
Michael Arnold

608-262-3863

Robert Jacobberger

(402) 250-2752

Copyright © University of Wisconsin-Madison

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Graphene/ Graphite

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Govt.-Legislation/Regulation/Funding/Policy

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Institute for Nanoscience hosts annual proposal planning meeting May 16th, 2025

Rice researchers harness gravity to create low-cost device for rapid cell analysis February 28th, 2025

Chip Technology

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Programmable electron-induced color router array May 14th, 2025

Enhancing power factor of p- and n-type single-walled carbon nanotubes April 25th, 2025

Ultrafast plasmon-enhanced magnetic bit switching at the nanoscale April 25th, 2025

Discoveries

Researchers unveil a groundbreaking clay-based solution to capture carbon dioxide and combat climate change June 6th, 2025

Cambridge chemists discover simple way to build bigger molecules – one carbon at a time June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Materials/Metamaterials/Magnetoresistance

Researchers unveil a groundbreaking clay-based solution to capture carbon dioxide and combat climate change June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Institute for Nanoscience hosts annual proposal planning meeting May 16th, 2025

Superconductors: Amazingly orderly disorder: A surprising effect was discovered through a collaborative effort by researchers from TU Wien and institutions in Croatia, France, Poland, Singapore, Switzerland, and the US during the investigation of a special material: the atoms are May 14th, 2025

Announcements

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Researchers uncover strong light-matter interactions in quantum spin liquids: Groundbreaking experiment supported by Rice researcher reveals new insights into a mysterious phase of quantum matter December 13th, 2024

New discovery aims to improve the design of microelectronic devices September 13th, 2024

Physicists unlock the secret of elusive quantum negative entanglement entropy using simple classical hardware August 16th, 2024

Atomic force microscopy in 3D July 5th, 2024

Research partnerships

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Superconductors: Amazingly orderly disorder: A surprising effect was discovered through a collaborative effort by researchers from TU Wien and institutions in Croatia, France, Poland, Singapore, Switzerland, and the US during the investigation of a special material: the atoms are May 14th, 2025

HKU physicists uncover hidden order in the quantum world through deconfined quantum critical points April 25th, 2025

SMART researchers pioneer first-of-its-kind nanosensor for real-time iron detection in plants February 28th, 2025

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project