graphene
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IBM shows off 155GHz graphene transistor in the name of DARPA research
IBM might be cautious about touting graphene as a a silicon killer, but that hasn't stopped it from pushing the production of ever faster graphene transistors. With the recent demonstration of a 155GHz graphene transistor, the firm successfully outdid its previous record-setting efforts, which produced a cut-off frequency of 100GHz. What's more, the thing is also IBM's smallest to date, with a gate length of 40 nanometers; that's 200 nanometers less than the 100GHz iteration. This smaller, faster transistor was produced as part of a DARPA research project that aims to develop high-performance RF (radio frequency) transistors. So, no, we probably won't be seeing the things in our PCs anytime soon, but it looks like they could be right at home in war machines of the future.
Researchers find graphene transistors cool themselves, silicon counterparts seethe with envy
We've seen graphene promise some pretty slick tricks already: budget-minded bendable batteries, superior stain resistance, and upping ultracapacitors' energy density. We can now add self-cooling transistors to the list of awesome, yet unfulfilled possibilities for these microscopic sheets of carbon. Using an atomic force microscope, a team of researchers at the University of Illinois led by Professor William King discovered that graphene transistors have a thermoelectric cooling effect where they make their metal connections. This self-cooling is greater than the resistive heating that normally follows the flow of electrons -- meaning graphene-based electronics from the future could make their silicon competition look decidedly uncool in comparison.
Silicine might be the new graphene, now that it's been physically constructed
Surely you've heard of graphene, the one-atom-thick layer of pencil lead that has the potential to change the world of computers, batteries and screens? You might want to familiarize yourself with the term "silicine," too. It's basically a version of graphene constructed out of silicon, which doesn't naturally align itself into the same eminently useful honeycomb shape -- but, given a little prod here and a layer of silver or ceramic compound there, can do much the same thing, and with better computing compatibility. First proposed around 2007, it's reportedly been produced twice now by two different teams, which gives physicists hope that it could actually be useful some day. For now, researchers need to figure out a way to easily produce it so detailed experiments can be performed -- from what we understand, the good ol' scotch tape method just won't do the job.
Flexible batteries get the graphene treatment, could be cheaper than other bendy batts
We've been talking about flexible batteries for years now, but a team of Korean researchers have presented a new solution to bendable energy sources that is not only more powerful than standard lithium-ion batteries, but also potentially cheaper to produce than its malleable predecessors -- and unsurprisingly, everyone's favorite wonder material, graphene, is at the heart of the innovation. The rechargeable battery contains a vanadium-oxide cathode, grown on a sheet of graphene paper, an unidentified separator, and an anode made of lithium-coated graphene. According to the folks behind the new power source, it sports higher energy and power density, as well as a better cycle life than the literally stiff competition. Similar advances have also out-performed rigid lithium-ion batteries, but have enlisted carbon nanotubes, a material more expensive to produce than graphene. Of course, like all technological advances, we won't be seeing these things for years, if not decades, so you might as well get used to ye olde standard bearer.
Fuel cells get stronger, potentially cheaper with graphene, ITO
As the sustainable Juggernaut of fuel cell vehicles (FCV) powers ever forward, a group of scientists are cooking up ways to make the alternative energy source more durable and even cheaper. By combining graphene -- think pencil lead -- and indium tin oxide (ITO) nanoparticles, the team produced a catalytic material that is both stronger and more chemically active than the usual catalytic combo. Fuel cells typically use a chemical catalyst like platinum, sitting atop a base of black carbon or metal oxides, to break down oxygen and hydrogen gases, creating water in the process -- thing is, carbon is easily eroded by the resulting water, and metal oxides, while more stable, are less conductive. Using graphene -- which because of its porousness erodes less quickly -- in combination with the stable ITO and platinum nanoparticles, researchers have created what could be referred to as a super fuel cell -- a stronger, longer lasting, and potentially cheaper version of the alternative energy source. Unfortunately, without enough hydrogen filling stations, these super fuel cells won't come to anyone's rescue anytime soon.
Graphene coatings used to repel, attract water, could make Rain-X decidedly obsolete
Graphene looks poised to replace our silicon and our touchscreens, even fix our batteries. Now it's due for something perhaps a little less revolutionary: keep our pants clean. Physicist James Dickerson and a team of researchers at Vanderbilt University have created two ways to apply thin graphene sheets that either make them super-hydrophobic or super-hydrophilic. These alternate arrangements, termed "rug" and "brick," make the water bead up and run off or spread out and form incredibly thin sheets. Potential applications are windshields that don't need wipers, pants that cause red wine drops to just bounce off, and goggles that never, ever fog -- no buffing required.
IBM says graphene won't fully replace silicon in CPUs
As you may have been able to tell from the flurry of research that's occurred over the past few years (which has even resulted in a Nobel Prize), there's plenty of folks betting on graphene as the next big thing for computing. One of the big players in that respect has been IBM, which first opened up the so-called graphene bandgap and has created some of the fastest graphene transistors around, but is now sounding a slightly more cautious tone when it comes to the would-be demise of silicon-based CPUs. Speaking with Custom PC, IBM researcher Yu-Ming Lin said that "graphene as it is will not replace the role of silicon in the digital computing regime," and further explained that "there is an important distinction between the graphene transistors that we demonstrated, and the transistors used in a CPU." To that end, he notes that unlike silicon, "graphene does not have an energy gap," and that it therefore cannot be completely "switched off," which puts it at quite a disadvantage compared to silicon. Intel's director of components research, Mike Mayberry, also chimed in on the matter, and noted that "the industry has so much experience with it that there are no plans to move away from silicon as the substrate for chips." That doesn't mean that there still isn't a bright future for graphene, though -- Lin gives the example of hybrid circuit, for instance, which could use graphene as a complement to silicon in order to "enrich the functionality of computer chips."
Graphene electrodes promise 5x energy storage boost for ultracapacitors
Graphene. We hear of your achievements so often, but feel your benefits in our everyday lives so infrequently. We'd be remiss if we didn't point out how unhealthy of a relationship this is, but hopefully Bor Jang and co. have a mind to mend it all. Bor, along with a number of colleagues at Nanotek Instruments, have just uncovered a graphene advancement that could put conventional Li-ion cells in a world of hurt. Of course, we've been hearing about so-called "battery breakthroughs" for the better part of our lives, but few have involved progress with ultracapacitors. For those unaware, ultracapacitors are energy storage devices that can "absorb and release charge in minutes," and they're pegged as cheaper / safer alternatives to batteries for electric vehicles. The only problem? Mainstream versions today hold just five percent of the energy held by Li-ion batteries. Nanotek's crew has figured out that the use of graphene electrodes "could lead to ultracapacitors with more than five times the energy density of commercial devices," but as these things always go, no one's coming close to producing a hard release date. We'll just assume it's undergoing lab tests for now, and in 2022 we can all weep at what could've been. Prove us wrong, whiz kids.
Nobel Prize in Physics awarded to pioneering graphene researchers
Last year's Nobel Prize in Physics may have been somewhat belatedly awarded to the inventors of the CCD, but this year's prize couldn't be more timely -- it's just been awarded to Russian-born researchers Andre Geim and Konstantin Novoselov for their "groundbreaking experiments" with graphene. Graphene, as you may well be aware by now, is the thinnest and lightest material there is, and could well pave the way for whole new generation of smaller, better, faster electronics -- among a host of other things. What's more, like so many great inventions, this one also had something of an inauspicious beginning -- the researchers kick-started their research just six years ago by peeling some flakes off a chunk of graphite with a piece of Scotch tape. [Thanks, Eddie]
Strained graphene leads to pseudo-magnetic fields, bends physics even further
Man, if only this had been discovered before Ariadne was tasked with building impossible dreams. A team of scientists caught high-fiving over at Lawrence Berkeley National Laboratory have a new and riveting announcement to share, and it revolves around our old and trusted friend, graphene. This go 'round, the self-proclaimed "extraordinary form of carbon" is being stressed to its max, but not without good reason. Thanks to inquisitive minds and a "stroke of serendipity," a research team was able to create magnetic fields in excess of 300 tesla by simply straining graphene in a certain way. For physicists, the discovery is a dream come true, particularly when you realize that magnetic fields in excess of 85 tesla were practically impossible to come across in a laboratory setting. The benefits here? It's honestly too early to tell, but gurus in the field are already suggesting that the "opportunities for basic science with strain engineering [are] huge." Something tells us Magneto would concur.
Silicon chips get speed boost with a lead start
In tennis, the materials of the tennis court affect the performance of the ball. Such is the case, on a much, much smaller scale, for electron movement across circuitry. Silicon chips give resistance that lowers the speed limit, while atom-thick sheets of carbon (a.k.a. graphene) have a special property whereby free electrons are almost weightless and can travel up to 0.003 times the speed of light -- sounds great, but it's hard to produce in bulk. Cut to Han Woong Yeom and Pohang University of Science and Technology in South Korea. His team has added a thin layer lead on a silicon chip, lowering the electron mass (and thus proportionally raising its speed) to 1/20th compared to standard silicon. Still a ways to go for graphene speeds -- by a factor of three, according to Yeom -- but it's also more likely to mass production.
Graphene rolled out in 30-inch sheets, makes for one durable touchscreen (video)
Whether they're slated to power terahertz chips or transparent electrodes, graphene sheets have garnered tremendous excitement, but the scientific community has had great trouble making the single-atom-thick pencil lead lattices large enough for industrial use. Thankfully, the same South Korean scientists who brought us 10 centimeter film never abandoned their post, and now Sungkyunkwan University has composited 30-inch sheets of the stuff and prototyped a working touchscreen panel as well. Using a modified version of the popular chemical vapor disposition deposition (CVD) technique that grows the graphene on top of copper foil, they were able to produce a four-ply graphene stack with 90 percent transparency, plus resistance and durability reportedly superior to the dwindling indium supplies currently used in displays. Now let's see some 300mm wafers, eh? Watch one of the world's first graphene digitizers make its video debut after the break.
Defective graphene sheets look poised to succeed silicon
As circuitry gets smaller and approaches the effective limitation of silicon's computing power, and Moore's Law begins to look like it has an expiration date, we get closer and closer to needing an alternative. Graphene is held to be the answer; sheets of carbon a single atom thick that could be stacked and composited to create processors. Two professors at the University of South Florida, Matthias Batzill and Ivan Oleynik, have found a new way to turn those sheets into circuits by creating nanoscale defects. These strips of broken atomic rings wind up having metallic properties, thus making them act like microscopic wires. IBM is already teasing us with the possibilities of graphene and now, with a more practical way to make graphene-based electronics, we'd say Moore's Law still has at least another couple decades left. [Photo credit: Y. Lin]
IBM demonstrates 100GHz graphene transistor
It's just been a little over a week since IBM researchers announced that they managed to open up a bandgap for graphene-based field-effect transistors, but they're now already back to show off what that's made possible: a 100GHz graphene transistor. What's more, this latest record-setting transistor (which IBM hopes will one day replace silicon transistors) was made using processing technology that's compatible with that currently used in advanced silicon device fabrication, which should no doubt help speed up its eventual commercialization. Of course, any widespread adoption is still quite a ways away, but IBM says that this new transistor "demonstrates clearly that graphene can be utilized to produce high performance devices and integrated circuits." For those keeping score, this first-of-its-kind transistor already beats the frequency performance of current state-of-the-art silicon transistors of the same gate length, which now top out at a mere 40GHz.
Penn State busts out 100mm graphene wafers, halcyonic dream inches closer to reality
Yes, we've been marching on this road to graphene-based superconductive electronics for a long, long time. But in the space of one week, we've now seen two significant advancements pop up that rekindle our hope for an ultrafast tomorrow. Hot on the heels of IBM's recent bandgap achievement comes Penn State University with a 100mm wafer of pure graphene gorgeousness. Built using silicon sublimation -- a process of essentially evaporating the silicon away from the carbon layer -- these are the biggest graphene wafers yet, and field effect transistors are being built atop them now to start performance testing early this year. Naturally, nobody's sitting on this laurel just yet, with further plans afoot to expand beyond 200mm wafers in order to integrate fully into the semiconductor industry, whose current standard wafer size is around 300mm in diameter. On we go then.
IBM opens up graphene bandgap, edges closer to commercialization
Graphene transistors have long been touted as the next big thing to deliver a true leap in electronics of all sorts, but there's been a few considerable limitations holding them back from fully replacing silicon. IBM now says it's managed to overcome one of the biggest hurdles, however, and has announced that it's been able to open a "bandgap" for graphene field-effect transistors (or FETs). As EETimes reports, that's important because while graphene does have a higher carrier mobility than silicon, it doesn't have a natural bandgap, which has so far kept the on-off ratio of graphene transistors far lower than their silicon counterparts. Of course, IBM insists that its still only just scratched the surface, and says that it's already hard at work on opening up an even wider bandgap, achieving even higher electric fields, further improving the on-off current ratios of graphene FETs.
Cornell gurus look to carbon nanotubes for efficient solar cells
You know what we love? Solar-powered gadgets, and carbon nanotubes. Oh, and Ivy League schools. Boffins from Cornell University are now looking to use the multifaceted carbon nanotube instead of silicon to develop efficient solar cells, and judging by the glacial pace at which solar cell efficiency is improving, we'd say the sector could use the boost. The researchers have already fabricated, tested and measured a simple solar cell (called a photodiode, just so you know) that was formed from an individual carbon nanotube. The tube was essentially a rolled-up sheet of graphene, and while the inner workings would take days to explain, the gist of it is this: "The nanotube may be a nearly ideal photovoltaic cell because it allowed electrons to create more electrons by utilizing the spare energy from the light."So, solar-powered F-350 trucks are now a possibility for next year, right?[Via Graphene-Info]
Carbon ring storage promises 1,000 times higher memory density
Terrifying news, kids: we're growing seriously close to maxing out the density limits of present magnetic memory technology as it becomes increasingly difficult to shrink the necessary grains used in the process. Thankfully, there's a team of German scientists devoted to doing more than standing around and watching the inevitable happen. Cobalt, the element responsible for keeping your precious data intact, typically requires a 50,000 atom fleet for each grain, but boffins from Dresden have found a way to shrink that to a measly flotilla of 50. Without trampling you with technological details, attaching carbon rings to the cobalt reproduces the requisite hexagonal close packed structure, which leads to reduced space requirements. Should this technique prove viable, we can expect yet another race among hard drive makers as they strive to make each other's most capacious drives look downright diminutive. Hit the read link for all the grisly details.[Via Graphene-Info]
Graphene chip could hit 1,000GHz, make your Core i7 feel totally inadequate
8GHz (with the help of liquid nitrogen) not quick enough? Leave it to the folks at MIT to make sure your zaniest desires are well taken care of. As research forges ahead on graphene, carbon nanotubes and buckyballs (remember those?), gurus at the university have discovered a breakthrough that could eventually lead to microchips that make existing silicon-based CPUs weep. In fact, the research could lead to practical systems in the 500 to 1,000 gigahertz range. The magic all ties back to advancements on a graphene chip known as a frequency multiplier, and while the nitty-gritty of all this is far too complicated for the layperson to grasp, all you really need to know is this: finally, you can rest assured that you'll one day own a chip capable of handling Duke Nukem Forever.[Via InformationWeek]
South Korean scientists get one step closer to graphene-based gadgets
Graphene-based gadgets are coming, we just know it. Trouble is, we're still a long, long ways away. That said, a team of South Korean scientists are bringing us ever closer to bendable, durable gizmos by creating a graphene film with a diameter of 10 centimeters by "adopting a conventional chemical vapor deposition (CVD) technique." Furthermore, the crew's development of what's being called the "world's first circuit patterning technology for the graphene film has the potential to replace silicon-based semiconductors." If this is just way too heavy for your mind to digest on a Friday, here's the skinny: the newfangled manufacturing process has, for all intents and purposes, overcome the limitations of graphene, which could not be made large enough for commercial applications in the past. [Image courtesy of ScienceFriday, thanks Agustin]
