Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > New rapid synthesis developed for bilayer graphene and high-performance transistors: UCSB researchers demonstrate ultra-fast and deterministic growth of high-quality and large-area bilayer graphene films with controlled stacking order required for low-power digital electronics

This is concept art of a schematic view of an AB-stacked graphene film synthesized by UC Santa Barbara researchers using a stoichiometry engineered bifunctional alloy catalyst.

Credit: Peter Allen, UCSB
This is concept art of a schematic view of an AB-stacked graphene film synthesized by UC Santa Barbara researchers using a stoichiometry engineered bifunctional alloy catalyst.

Credit: Peter Allen, UCSB

Abstract:
Researchers at University of California, Santa Barbara, in collaboration with Rice University, have recently demonstrated a rapid synthesis technique for large-area Bernal (or AB) stacked bilayer graphene films that can open up new pathways for digital electronics and transparent conductor applications.

New rapid synthesis developed for bilayer graphene and high-performance transistors: UCSB researchers demonstrate ultra-fast and deterministic growth of high-quality and large-area bilayer graphene films with controlled stacking order required for low-power digital electronics

Santa Barbara, CA | Posted on May 3rd, 2014

The invention also includes the first demonstration of a bilayer graphene double-gate field-effect transistor (FET), showing record ON/OFF transistor switching ratio and carrier mobility that could drive future ultra-low power and low-cost electronics.

Graphene is the thinnest known (~0.5 nanometer per layer) 2-dimensional atomic crystal. It has attracted wide interest due to its promising electrical and thermal properties and potential applications in electronics and photonics. However, many of those applications are significantly restricted by the zero band gap of graphene that results in leaky transistors not suitable for digital electronics.

"In addition to its atomically smooth surfaces, a considerable band gap of up to ~0.25 eV can be opened up in bilayer graphene by creating a potential difference between the two layers, and thereby breaking the inherent symmetry, if the two layers can be aligned along a certain (Bernal or AB) orientation" explained Kaustav Banerjee, professor of electrical and computer engineering and Director of the Nanoelectronics Research Lab at UCSB. "The dual-gated transistors were specifically designed to allow such potential difference to be established between the layers through one of the gates, while the second gate modulated the carriers in the channel," he added. Banerjee's research team also includes UCSB researchers Wei Liu, Stephan Kraemer, Deblina Sarkar, Hong Li and Professor Pulickel Ajayan of Rice University. Their study was recently published in Chemistry of Materials.

The graphene films were grown in a deterministic manner using an engineered bifunctional (Cu:Ni) alloy surface at a relatively low temperature of 920 įC. Large-area (> 3 inch ◊ 3 inch) Bernal (or AB) stacked bilayer graphene growth was demonstrated within few minutes and with nearly 100% area coverage. The bilayer graphene films exhibited electron mobility as high as 3450 cm2/(Vēs), which is comparable to that of exfoliated bilayer graphene, thereby confirming very high-quality. The quality of grown graphene was further corroborated by demonstration of high-performance FETs with record ON/OFF ratio that is a key requirement in low-power digital electronics.

"Achieving surface catalytic graphene growth mode and precise control of the surface carbon concentration were key factors for the favorable growth kinetics for AB stacked bilayer graphene," explained Wei Liu, a post-doctoral researcher in Banerjee's group and a co-author of the article. In 2011, Banerjee's group demonstrated a large-area monolayer graphene synthesis method using a copper substrate as catalyst.

Bilayer graphene is close to monolayer graphene in terms of the film thickness with a hexagonal atomic structure and can be derived from its layered bulk form (graphite) in which adjacent layers are held together by relatively weak van der Waals forces. "However, apart from its band gap tunability, bilayer graphene has some key advantages over monolayer graphene. It has higher density of states and suffers much less from interface effects, which are beneficial for improving the current carrying capability," Liu continued.

"This demonstration is very impressive and should have far-reaching implications for the entire 2D materials community," commented Professor Ali Javey, of University of California, Berkeley and a Co-Director of the Bay Area Photovoltaic Consortium (BAPVC).

###

Their research was supported by the Bay Area Photovoltaic Consortium (BAPVC) a U.S. Department of Energy funded Photovoltaic Consortium, the California NanoSystems Institute at UC Santa Barbara, and the Materials Research Laboratory at UCSB: a National Science Foundation MRSEC.

####

About University of California - Santa Barbara
The College of Engineering at University of California, Santa Barbara is recognized globally as a leader among the top tier of engineering education and research programs, and is renowned for a successful interdisciplinary approach to engineering research. www.engineering.ucsb.edu

For more information, please click here

Contacts:
Melissa Van De Werfhorst

Copyright © University of California - Santa Barbara

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

NREL Announces New Center Directors to lead R&D, Analysis Efforts September 30th, 2014

Yale University and Leica Microsystems Partner to Establish Microscopy Center of Excellence: Yale Welcomes Scientists to Participate in Core Facility Opening and Super- Resolution Workshops October 20 Through 31, 2014 September 30th, 2014

Speed at its limits September 30th, 2014

Research mimics brain cells to boost memory power September 30th, 2014

Graphene

Elsevier Publishes New Content on Graphene and Materials Science: Books Discuss Properties and Emerging Applications of Carbon Nanotubes, Graphene and Nanomaterials September 25th, 2014

Graphene and Amaranthus Superparamagnets: Breakthrough nanoparticles discovery of Indian researcher September 23rd, 2014

Southampton scientists grow a new challenger to graphene September 23rd, 2014

Twisted graphene chills out: When two sheets of graphene are stacked in a special way, it is possible to cool down the graphene with a laser instead of heating it up, University of Manchester researchers have shown September 22nd, 2014

Govt.-Legislation/Regulation/Funding/Policy

NREL Announces New Center Directors to lead R&D, Analysis Efforts September 30th, 2014

A Heartbeat Away? Hybrid "Patch" Could Replace Transplants: TAU researcher harnesses gold nanoparticles to engineer novel biocompatible cardiac patch September 30th, 2014

How things coil: Researchers discover that simulation technology designed for Hollywood can be used as a predictive tool for understanding fundamental engineering problems September 29th, 2014

UT Arlington researchers develop transparent nanoscintillators for radiation detection for medical safety and homeland security September 29th, 2014

Chip Technology

Speed at its limits September 30th, 2014

Research mimics brain cells to boost memory power September 30th, 2014

'Pixel' engineered electronics have growth potential: Rice, Oak Ridge, Vanderbilt, Penn scientists lead creation of atom-scale semiconducting composites September 29th, 2014

Future flexible electronics based on carbon nanotubes: Study in Applied Physics Letters show how to improve nanotube transistor and circuit performance with fluoropolymers September 23rd, 2014

Nanoelectronics

Grenoble Hosting SEMICON Europa Oct. 7-9, First Time Event Held in France: Letiís 90-square-meter Booth Will Feature Portable Showroom To Demonstrate New Technology Innovations September 24th, 2014

SouthWest NanoTechnologies (SWeNT) Receives NIST Small Business Innovation Research (SBIR) Phase 1 Award to Produce Greater than 99% Semiconducting Single-Wall Carbon Nanotubes September 19th, 2014

Rice rolls 'neat' nanotube fibers: Rice University researchers' acid-free approach leads to strong conductive carbon threads September 15th, 2014

Excitonic Dark States Shed Light on TMDC Atomic Layers: Berkeley Lab Discovery Holds Promise for Nanoelectronic and Photonic Applications September 11th, 2014

Discoveries

Research mimics brain cells to boost memory power September 30th, 2014

Ad-REIC vaccine: A magic bullet for cancer treatment September 30th, 2014

New Topical Hemostatic Agent: Neutral Self-Assembling Peptide Hydrogel September 30th, 2014

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

Announcements

Park Systems Announces Outsourced Analytical Services Including AFM Surface Imaging, Data Analysis and Interpretation September 30th, 2014

Ad-REIC vaccine: A magic bullet for cancer treatment September 30th, 2014

New Topical Hemostatic Agent: Neutral Self-Assembling Peptide Hydrogel September 30th, 2014

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals

Speed at its limits September 30th, 2014

Ad-REIC vaccine: A magic bullet for cancer treatment September 30th, 2014

New Topical Hemostatic Agent: Neutral Self-Assembling Peptide Hydrogel September 30th, 2014

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

Research partnerships

Research mimics brain cells to boost memory power September 30th, 2014

'Pixel' engineered electronics have growth potential: Rice, Oak Ridge, Vanderbilt, Penn scientists lead creation of atom-scale semiconducting composites September 29th, 2014

Teijin Aramidís carbon nanotube fibers awarded with Paul Schlack prize: New generation super fibers bring wave of innovations to fiber market September 25th, 2014

Smallest-possible diamonds form ultra-thin nanothread September 25th, 2014

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



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE