Arthur S. Davis National University 10/23/2013
The evolution of computers replacing mechanical and electrical relays with vacuum tubes, then transistors and eventually finely sculpted silicon wafers is about to see a new transformation. Using a material so common that it is part of almost everything we see, touch, eat or breathe, scientists and engineers are busy making products that will warp our vision of the future. Carbon is as old as the hills and in its newest form it could quickly eclipse previous advancements in computer processing and storage. Computer circuits will soon become smaller, faster and more resilient in extreme environments because they will be made from one of the strongest materials in the world.
Carbon comes in two forms that we can instantly recognize: graphite as in charcoal or coal and diamonds. Their chemical properties seem opposed to each other but they both possess qualities that make them uniquely strong and resilient. Diamonds are beautiful and romantic; aligned with the rich and famous, young lovers and long marriages. Conversely, graphite seems tenuous, slippery and filthy; good for burning as fuel or making pencils. However, if we look into the chemical properties of the two we can better understand why the flexible and self-aligning properties of graphite make it a best choice for many products today.
Diamonds find their strength and beauty through the way the individual carbon atoms are associated. Carbon atoms have four outer electrons. In a diamond each outer electron of a carbon atom is shared with other neighboring atoms. Because no electrons are left over for conduction, diamonds are a good insulator and they are transparent because light cannot easily excite and be absorbed by the well bonded electrons. The atomic structure of a diamond gives it the hardness to be cut and polished into beautiful shapes for jewelry and extreme sharpness for cutting tools.
On first inspection, graphite exhibits the qualities of a very soft material. Anyone handling charcoal or coal will find it rubbing off and spreading to everything it touches. This "softness" is caused by the way carbon atoms are composed in graphite. Only three of the outer electrons form bonds with other carbon atoms. The three-way bond forms a sheet of interlocked hexagonal structures leaving one electron of each atom to form a weaker bond to other sheets of carbon atoms. The weak bond between sheets creates the quality that allows graphite to be transferred easily to another surface. This can be demonstrated when writing with a number two pencil. However, the bonds within the sheet are much stronger. Only one atom thick, a sheet of linked carbon atoms could be made into a hammock that would swing a small cat ( Neto & Geim, 2012).
In 2004, Andre Geim and Konstantin Novosolev of the University of Manchester leveraged the transferable quality of graphite by using adhesive tape to isolate a one-atom thick layer of graphite (Wright, 2013). Dubbed graphene, the material has attracted the interest of many scientists and electronics engineers, including the IBM company which produced the first integrated circuit using graphene based transistors (Savage, 2011). In addition to the amazing physical qualities, graphene's perfect honeycomb structure promotes extreme electrical conductivity. Electrons can move about with almost no resistance; up to 500 times faster than silicon used in current computer circuits (Wright, 2013). IBM's team used this superconductive property to double the speed of comparable sized silicon components and they predict much greater improvements. Additionally, the material qualities of graphene could enable it to be stitched into clothing as a cellphone or GPS receiver. Considering these few examples, the possibilities for new applications are great.
Currently, the production of graphene and graphene based electronics is expensive. At 3,000 dollars per square meter, the price can be discouraging to manufacturers (Wright, 2013). We can only imagine the cost for an expert team of researchers at IBM to develop a single broadband radio-frequency mixer. Conversely, IBM's team used "conventional" electron beam lithography combined with a few simple chemical processes to create the circuit. This indicates that current manufacturing processes could be easily modified to produce graphene based circuits. Additionally, graphene can be derived from readily available graphite oxide by a washing process using green friendly alcohol to replace THF, dioxane, C1-C6 dialkyl ethers, phenols, ketones, et al used in electronics manufacturing (method, 2013). Ease of manufacturing and other qualities such as excellent heat tolerance that can simplify circuit designs point to graphene's future dominance in the electronics industry (Wright, 2013).
In a development parallel to IBM's, a group from UCLA has produced circuits by growing the graphene on a glass plate through chemical vapor deposition (CVD) while using an electrical field to align a single nanowire for use as a gate in the transistors (Liao, Bai et al, 2012). The group eschews the use of silicon as a limiting factor because of parasitic capacitance. In other words, the current best choice for electrical circuits is too leaky and inefficient when compared to graphene. Similar to IBM, this experiment provides performance measurements that far outshine silicon based circuits and cites inefficiencies in measurement as limiting better results. To list this development as "promising" is an understatement. The UCLA group has produced a scalable product that can be adapted to any circuit currently in use.
It is interesting to consider the dark and dirty coal as the light at the end of the tunnel for technological advancement but it is exactly that. The carbon atoms carried in a lump of coal are the same as those present in expertly designed micro-circuits. Additionally, the processes associated with creating graphene based circuits appear to counter previous electronics manufacturing proven dangerous to the environment. Altogether, the prospects for graphene to become the champion of technological advancement are great. Very soon, the diamonds lowly cousin will be worth its weight in gold.
Liao, L., Bai, J., Cheng, R., Zhou, H., Liu, L., Liu, Y., Huang, Y. & Duan, X. (2012, June 13) Scalable fabrication of self-aligned graphene transistors and circuits on glass. NIH Public Access. Retrieved from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3269556/
Method of Producing Graphene Oxide and its Uses in Patent Application Approval Process. (2013). Life Science Weekly, , 2373. Retrieved from http://ezproxy.nu.edu/login?url=http://search.proquest.com/docview/1418232336?accountid=25320
Neto, A. C. & Geim, A. (2012, May 5). Graphene. New Scientist . 214( 2863), i-8.
Savage, N. (2011, June 9). First Graphene Integrated Circuit. IEEE Spectrum. Retrieved from: http://spectrum.ieee.org/semiconductors/devices/first-graphene-integrated-circuit
Wright, A. (2013, October). Tuning in to graphene. Communications of the ACM. 56(10). 15-17.
The notion of computers invading our privacy is a hot topic in today's news. The internet is littered with warnings about the NSA digging into our lives and the IRS has acted on the data in a most alarming way. The U.S.A Patriot Act (2001), in an attempt to fight terrorism on U.S. soil has weakened the Fourth amendment of the U.S. Constitution which protects people from "unreasonable searches and seizures" and requires a warrant backed by "…[o]ath or affirmation…" that lists particular "…places to be searched, and…things to be seized" (Bill of Rights, 1791). The NSA's methods, leaked by former employee Edward Snowden and posted on Wikileaks give a clear view of the type and scope of information our government is currently collecting More...
For over two thousand years school reform has produced positive results while failing to provide a simple and effective program to encourage innovative thinkers. It is easy to craft a solution, limited by our grasp of the facts and their application, which can become ineffective when viewed from another perspective or vetted through trial and error. Today, the biggest problem is that we spend all of our time on the acquisition and review of knowledge, and the goal of innovation has been suspended. Effective class time utilization offers a solution by providing a small space in the curriculum for new ideas. Allowing inspiration to enter the classroom is all that is needed to extract the nectar of innovation from the flower of knowledge.More...
We are living on a planet with finite natural resources and an exploding human population. The need for efficiency in all things is increasing every day. We are forced to comply with inarguable logic that compares the needs of humanity with available and realistic solutions. Green Computing, a more recent trend in computer science, promises to promote efficiency by analysis and implementation of "earth friendly" solutions to limit waste in the design, manufacturing and operation of computers. Green Computing can include anything from bicycle powered PDA's to giant server farms squeezing out a few watts per node. In all of its forms, Green Computing uses efficiency as a tool to limit human impact on our environment. More...
Of all the mathematical theorems, postulates and conjectures, the Fibonacci sequence stands out as the most useful modern tool devised by the ancient mathematicians. Its simplicity makes it accessible to the student or layman. Its application in finance or search algorithms gives it credence among exceedingly complex calculations. It is also a romantic notion, easily repeated like a popular song with a great history. Like Pythagoras or Euclid, Leonardo "Fibonacci" di Pisa brought complex mathematics into popular knowledge and he has been repaid by the enormous use of his product. More...