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On the cusp of new materials development, graphene materials could revolutionize the technology industry
Today's technology, which is based on silicon development, has nearly reached its limit. While silicon is a useful material, it's not boundless. What this means is without new materials, the increase in technology efficiency will end and seriously impact the American economy. Dr. Walt de Heer at Georgia Institute of Technology in Georgia has a solution. He is researching the enormous potential that graphene materials can bring to the electronics industry. Specifically to target three important aspects of design: size, heat and speed.
Size - graphene can be reduced to sizes as small as a few nanometers - ten times smaller than the smallest sizes silicon can reach.
Heat- the transfer of heat with graphene is much more efficient which will keep computers from overheating.
Speed -graphene appears to be able to work at terahertz speed, 1000 times faster than gigahertz.
In the past decade Dr. de Heer's team have made tremendous strides in developing graphene electronics and graphene science. They are recognized as world leaders in the field.
Recently they have overcome several of the greatest impediments towards further progress, which is a demonstration of ballistic transport in graphene nanostructures, the development of record breaking prototype transistor devices, and the development of a viable semiconducting form of graphene, which is an enabling step to produce digital electronics.
He estimates that proof of principle devices will be demonstrated within 2 years in optimal conditions (that is, transistors that significantly out-perform silicon in at least one key property: speed, size, heat dissipation). In the same time frame he expects to demonstrate the viability of graphene electronics for operation in extreme conditions (i.e. high temperature environments, or high radiation environments).
Dr. de Heer's current research focuses on producing extremely fast graphene transistors, as well as developing a new form of semiconducting graphene as well as a new kind of graphene transistor based on quantum mechanical "tunneling". They use silicon carbide (which is a very important semiconductor in the electronics industry) as the foundation for the graphene. They have developed methods to "grow" the graphene directly on the silicon carbide. This produces the highest quality graphene in the world and the methods can be used on an industrially relevant scale.
They are also working to understand the basic physics of graphene electronics. In particular, they have strong evidence that the carriers of currents in our graphene are not the usual electrons and holes, but actually combinations of the two, thereby, in some sense, mimicking the current carriers in superconductors. Verification of this will constitute a revolutionary breakthrough in electronics.
Dr. de Heer's research has a real chance of revolutionizing electronics. It is well known, that silicon based electronics is running out of steam. Miniaturization and heat production is has reached its limits. Moreover, the speed that silicon transistors can operate cannot be increased any further. The upshot is, that silicon based electronics will plateau. A new electronics platform, like that offered by graphene, can restart the process again, with a revolution comparable to the silicon revolution of the last 50 years.
While Dr. de Heer does not believe that graphene will replace silicon, it is likely that it will outperform it. Much in the same way that airplanes have revolutionized transportation without replacing cars and boats.
Since the Georgia Institute of Technology owns the key patents, and since they are the world leaders in silicon carbide based graphene electronics (which is currently the only viable graphene electronics platform) they are clearly the ones to push this technology forward. However, as it stands, with the current innovation deficit, it is not unlikely that within a few years this technology will be taken over by China, Korea, and the EU.
Bio
Dr. Walt de Heer earned a doctoral degree in Physics from the University of California, Berkeley in 1986 under the supervision of Walter D. Knight. He worked at the Ecole Polytechnique Federale de Lausanne in Switzerland from 1987 to 1997, and is currently a Regents' Professor of Physics at the Georgia Institute of Technology. He directs the Epitaxial Graphene Laboratory in the School of Physics and leads the Epitaxial Graphene Interdisciplinary Research Group at the Georgia Tech Materials Research Science and Engineering Center.
In 2006, de Heer was named as one of the "Scientific American 50", a list of individuals/organizations honored for their contributions to science and society during the preceding year.
In 2007, he and his research group were awarded the prestigious W.M. Keck Foundation grant for continuation of work on "nanopatterned epitaxial graphene electronic devices that work at room temperature."
De Heer received IBM Faculty Awards in 2007 and 2008, and his work on graphene transistors was named as one of Technology Review's 10 emerging technologies "most likely to change the way we live" in 2008.
In September 2009, de Heer was awarded the ACSIN Nanoscience Prize "for his visionary work in developing the field of graphene nanoscience and technology"
De Heer has been awarded the 2010 Materials Research Society Medal "for his pioneering contributions to the science and technology of epitaxial graphene".
Below is a timeline of important discoveries and events,
1983 Discovered electronic shell structure in alkali clusters.
1996 Discovered field emitting properties of carbon nanotubes films with display application
potential.
1998 Discovered of quantized, ballistic conductance at room temperature in carbon nanotubes.
2001 Initiated international graphene research program.
2003 Filed patent for the invention of graphene nanoelectronics, "Patterned thin film graphite devices and method for making same"US Patent 7,015,142
2003 Awarded INTEL grant for graphene research.
2004 Awarded NSF NIRT grant for graphene research
2004 Published the first paper on methods and properties of graphene.
2007- Awarded WM KECK foundation for epigraphene electronics research
2008 Established the NSF MRSEC center for graphene research
2014 Published the discovery of exceptional ballistic transport in graphene nanoribbons
Dr. de Heer has always been interested in physics, he tinkered with electronics since his early teens. He even built his own electric guitar, got into rock music (played "professionally" for some years).
He went to Berkeley with the intention to become an elementary particle physicist, but then got interested in the properties of nanoparticles in the early 1980. In his Ph.D. work, he discovered the fundamental electronic properties of metal nanoparticles. He continued this work in Switzerland and wrote the most highly cited review article on the subject. In Switzerland he became interested in carbon nanoparticles in the early 1990's. This interest expanded into an interest in carbon nanotubes. In 1996, he discovered that these carbon nanotubes are excellent field emitters and could be used for flat panel displays, which started research worldwide to produce these displays. De Heer got a position at the Georgia Institute of Technology in 1996 and continued his research on carbon nanotube work. In 1998, he discovered that the nanotubes were excellent conductors. Concurrently many people around the world were getting interested in the possibilities of carbon nanotube electronics. However de Heer realized that this kind of electronics had a fatal flaw, which is, that it is very difficult if not impossible to reliably produce billions of nanotube transistors on a single chip as is required in modern electronics.
It occurred to Dr. de Heer in 2001, that graphene could do the job of nanotubes and that, just like silicon, billions of graphene transistors could be placed on a single chip using modern electronics manufacturing methods.
Dr. de Heer's first funding came from Intel in 2003, who recognized this could be important. He also filed hisour patent then, which is the foundation patent for all graphene electronics and was awarded an NSF grant.
Dr. de Heer and his team are continuing their work on several fronts, from the basic science point of view and from the electronics applications perspective. They have built a strong international team and publish regularly in the best journals. In February 2014, they published a groundbreaking paper in Nature demonstrating the excellent properties of graphene "ribbons". This work mentioned in the opening lines of the inaugural speech of the new director of the French National Science foundation. The NSF also featured it on their website.
Regardless, sequestering has reduced our AFOSR funding by 50 % and our NSF funding was recently cut so that we are currently running on a bare bones budget.
At the same time, Korea, China and the EU are doubling up on graphene electronics research.
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