A flat layer of carbon atoms packed into a two-dimensional honeycomb arrangement, graphene is being touted as a miracle (it seems) material which will enable new kinds of electronic products. Recently, there have been a number of news items and articles featuring graphene research.
Here’s my roundup of the latest and greatest graphene news. I’m starting with an application that is the closest to commercialization: IBM recently announced the creation of the first graphene-based integrated circuit. From the Bob Yirka article dated June 10, 2011 on physorg.com,
Taking a giant step forward in the creation and production of graphene based integrated circuits, IBM has announced in Science, the fabrication of a graphene based integrated circuit [IC] on a single chip. The demonstration chip, known as a radio frequency “mixer” is capable of producing frequencies up to 10 GHz, and demonstrates that it is possible to overcome the adhesion problems that have stymied researchers efforts in creating graphene based IC’s that can be used in analog applications such as cell phones or more likely military communications.
The graphene circuits were started by growing a two or three layer graphene film on a silicon surface which was then heated to 1400°C. The graphene IC was then fabricated by employing top gated, dual fingered graphene FET’s (field-effect transistors) which were then integrated with inductors. The active channels were made by spin-coating the wafer with a thin polymer and then applying a layer of hydrogen silsequioxane. The channels were then carved by e-beam lithography. Next, the excess graphene was removed with an oxygen plasma laser, and then the whole works was cleaned with acetone. The result is an integrated circuit that is less than 1mm2 in total size.
Meanwhile, there’s a graphene research project in contention for a major research prize in Europe. Worth 1B Euros, the European Union’s 2011 pathfinder programme (Future and Emerging Technologies [Fet11]) in information technology) will select two from six pilot actions currently under way to be awarded a Flagship Initiative prize. From the Fet11 flagships project page,
FET Flagships are large-scale, science-driven and mission oriented initiatives that aim to achieve a visionary technological goal. The scale of ambition is over 10 years of coordinated effort, and a budget of up to one billion Euro for each Flagship. They initiatives are coordinated between national and EU programmes and present global dimensions to foster European leadership and excellence in frontier research.
To prepare the launch of the FET Flagships, 6 Pilot Actions are funded for a 12-month period starting in May 2011. In the second half of 2012 two of the Pilots will be selected and launched as full FET Flagship Initiatives in 2013.
Here’s the description of the Graphene Science and technology for ICT and beyond pilot action,
Graphene, a new substance from the world of atomic and molecular scale manipulation of matter, could be the wonder material of the 21st century. Discovering just how important this material will be for Information and Communication Technologies is the long term focus of the Flagship Initiative, simply called, GRAPHENE. This aims to explore revolutionary potentials, in terms of both conventional as well as radically new fields of Information and Communication Technologies applications.
Bringing together multiple disciplines and addressing research across a whole range of issues, from fundamental understandings of material properties to Graphene production, the Flagship will provide the platform for establishing European scientific and technological leadership in the application of Graphene to Information and Communication Technologies. The proposed research includes coverage of electronics, spintronics, photonics, plasmonics and mechanics, all based on Graphene.
Andrea Ferrari, Cambridge University, UK
Jari Kinaret, Chalmers University, Sweden
Vladimir Falko, Lancaster University, UK
Jani Kivioja, NOKIA, Finland [emphases mine]
Not so coincidentally (given one member of the team is associated with Nokia and another is associated with Cambridge University), the Nokia Research Centre jointly with Cambridge University issued a May 4, 2011 news release (I highlighted it in my May 6, 2011 posting [scroll down past the theatre project information]) about the Morph concept (a rigid, flexible, and stretchable phone/blood pressure cuff/calculator/and other electronic devices in one product) which they have been publicizing for years now. The news release concerned itself with how graphene would enable the researchers to take the Morph from idea to actuality. The webpage for the Graphene Pilot Action is here.
There’s something breathtaking when there is no guarantee of success about the willingness to invest up to 1B Euros in a project that spans 10 years. We’ll have to wait until 2013 before learning whether the graphene project will be one of the two selected as Flagship Initiatives.
I must say the timing for the 2010 Nobel Prize for Physics which went to two scientists (Andre Geim and Konstantin Novoselov) for their groundbreaking work with graphene sems interesting (featured in my Oct. 7, 2010 posting) in light of this graphene activity.
The rest of these graphene items are about research that could lay the groundwork for future commercialization.
Friday, June 13, 2011 there was a news item about foaming graphene on Nanowerk (from the news item),
Hui-Ming Cheng and co-workers from the Chinese Academy of Sciences’ Institute of Metal Research at Shenyang have now devised a chemical vapor deposition (CVD) method for turning graphene sheets into porous three-dimensional ‘foams’ with extremely high conductivity (“Three-dimensional flexible and conductive interconnected graphene networks grown by chemical vapour deposition” [published in Nature Materials 10, 424–428 (2011) doi:10.1038/nmat3001 Published online 10 April 2011]). By permeating this foam with a siloxane-based polymer, the researchers have produced a composite that can be twisted, stretched and bent without harming its electrical or mechanical properties.
Here’s an image from the Nature Publishing Group (NPG) of both the vapour and the bendable, twistable, stretchable composite (downloaded from the news item on Nanowerk where you can find a larger version of the image),
The ‘elastic’ conductor (image to the right) reminds me of the ‘paper’ phone which I wrote about May 8, 2011 and May 12, 2011. (It’s a project where teams from Queen’s University [in Ontario] and Arizona State University are working to create flexible screens that give you telephony, music playing and other capabilities much like the Morph concept.)
Researchers in Singapore have developed a graphene quantum dot using a C60 (a buckminster fullerene). From the June 13, 2011 news item (Graphene: from spheres to perfect dots) on Nanowerk,
An electron trapped in a space of just a few nanometers across behaves very differently to one that is free. Structures that confine electrons in all three dimensions can produce some useful optical and electronic effects. Known as quantum dots, such structures are being widely investigated for use in new types of optical and electronics technologies, but because they are so small it is difficult to fabricate quantum dots reproducibly in terms of shape and size. Researchers from the National University of Singapore (NUS) and A*STAR have now developed a technique that enables graphene quantum dots of a known size to be created repeatedly and quickly (“Transforming C60 molecules into graphene quantum dots” [published in Nature Nanotechnology 6, 247–252 (2011) doi:10.1038/nnano.2011.30 Published online 20 March 2011]).
This final bit is about a nano PacMan that allows for more precise patterning from a June 13, 2011 article written by Michael Berger,
A widely discussed method for the patterning of graphene is the channelling of graphite by metal nanoparticles in oxidizing or reducing environments (see for instance: “Nanotechnology PacMan cuts straight graphene edges”).
“All previous studies of channelling behavior have been limited by the need to perform the experiment ex situ, i.e. comparing single ‘before’ and ‘after’ images,” Peter Bøggild, an associate professor at DTU [Danish Technical University] Nanotech, explains to Nanowerk. “In these and other ex situ experiments the dynamic behavior must be inferred from the length of channels and heating time after completion of the experiment, with the rate of formation of the channel assumed to be consistent over the course of the experiment.”
In new work, reported in the June 9, 2011 advance online edition of Nano Letters (“Discrete dynamics of nanoparticle channelling in suspended graphene” [published in Nano Letters, Article ASAP, DOI: 10.1021/nl200928k, Publication Date (Web): June 9, 2011]), Bøggild and his team report the nanoscale observation of this channelling process by silver nanoparticles in an oxygen atmosphere in-situ on suspended mono- and bilayer graphene in an environmental transmission electron microscope, enabling direct concurrent observation of the process, impossible in ex-situ experiments.
Personally, I love the youtube video I’ve included here largely because it features blobs (as many of these videos do) where they’ve added music and titles (many of these videos do not) so you can better appreciate the excitement,
From the article by Michael Berger,
As a result of watching this process occur live in a transmission electron microscope, the researchers say they have seen many details that were hidden before, and video really brings the “nano pacman” behavior to life …
There’s a reason why they’re so interested in cutting graphene,
“With a deeper understanding of the fine details we hope to one day use this nanoscale channelling behavior to directly cut desired patterns out of suspended graphene sheets, with a resolution and accuracy that isn’t achievable with any other technique,” says Bøggild. “A critical advantage here is that the graphene crystal structure guides the patterning, and in our case all of the cut edges of the graphene are ‘zigzag’ edges.”
So there you have it. IBM creates the first integrated graphene-based circuit, there’s the prospect of a huge cash prize for a 10-year project on graphene so they could produce the long awaited Morph concept and other graphene-based electronics products while a number of research teams around the world continue teasing out its secrets with graphene ‘foam’ projects, graphene quantum dots, and nano PacMen who cut graphene’s zigzag edges with precision.
ETA June 16, 2011: For those interested in the business end of things, i.e. market value of graphene-based products, Cameron Chai features a report, Graphene: Technologies, Applications, and Markets, in his June 16, 2011 news item on Azonano.