Aston Martin One-77 in a Showrom in the Middle East. According to Autoblog , present only a single Aston Martin One-77 finally for sale.However, do not know the exact order the production of this car. This special version of Aston Martin are numbered from 1 to 77 production. 
One-77 using 7.3-liter V12 engine with a capacity of 750 horsepower, maximum torque of 678 Nm. By using these advanced materials, lighter engine 6 liter V12 versus about 10%. 
Energy transfer to the rear wheels via a 6-speed automatic transmission control lever mounted on the steering wheel. One-77 uses 20-inch seven-spoke wheels dual tires Pirelli P Zero Corsa 255/35 front and 335/30 rear. One-77 is accelerated to 100 km / h from the position in just 3.5 seconds, top speed 320 km / h. 
Aston Martin One-77 for full production in the form of a purchase order (bespoke ) and patrons can participate in all stages of product development. Solid chassis (monocoque) is made ​​entirely from carbon fiber. 
British carmaker Aston Martin One-77 sold worldwide, but primarily to customers from the Middle East, where the king of the world oil world. Time in the U.S. only from 5 to 8 the One-77. This particular sample car become a rare commodity in the world, along with price “crisis” more than $ 1.4 million in foreign markets.

Back in 1920 at ETH Zurich, the chemist Hermann Staudinger postulated the existence of macromolecules consisting of many identical modules strung together like a chain. His concept was initially greeted with mockery and incomprehension from his fellow chemists. But Staudinger was to be proved right (and eventually even awarded the Nobel Prize in Chemistry in 1953): today the macromolecules described as polymers are known as plastics, and by 1950 one kilogram of them was already being produced per capita worldwide. Today, more than ninety years after Staudinger’s discovery about 150 million tons of plastics are manufactured every year — a gigantic industry delivering products that our daily lives can hardly do without. A research group led by ETH Zurich scientists A. Dieter Schlüter and Junji Sakamoto has now succeeded in making a decisive breakthrough in the synthetic chemistry of polymers: they have for the first time created two-dimensional polymers.

Polymers are formed when small single molecules known as monomers join together by chemical reactions like the links of a chain to form high molecular weight substances. The question remained as to whether polymers can only polymerize linearly, i.e. in one dimension. Although graphene counts as a naturally occurring representative of a two-dimensional polymer — planar layers of carbon with a honeycomb-like pattern — it cannot be synthesized in a controlled way. In order to develop a synthetic chemistry that generates two-dimensional molecules the ETH chemists had to first and foremost create oligofunctional monomers in such a way that they join together purely two-dimensionally instead of linearly or even three-dimensionally. Polymers of this kind must have three or more covalent bonds between the regularly repeating units. The scientists had to find out which bonding chemistry and environment was most suitable for producing this kind of “molecular carpet.”

Light plus special building blocks equal a “molecular carpet”

They decided to do the synthesis in a single crystal, i.e. a crystal with a homogeneous layer lattice. PhD student Patrick Kissel successfully used this to crystallize special monomers in layered hexagonal single crystals. The monomers he generated are photochemically sensitive molecules, for which such an arrangement is energetically optimum. When irradiated with light with a wavelength of 470 nanometers, the monomers polymerized in all the layers of the crystal. To separate the individual layers from one another the researchers boiled the crystal in a suitable solvent. Each layer represents a two-dimensional polymer.

The fact that the team really had succeeded in producing sheet-like polymers with regular structures was shown by special studies in a transmission electron microscope (TEM) carried out by Empa researcher Rolf Erni and Marta Rossell from ETH Zurich (who meanwhile is also working at Empa’s Electron Microscopy Center). “These two-dimensional polymers are extremely sensitive towards irradiation. It’s really tricky to not destroy their structure during the TEM measurements, which made the analyses a real tough nut to crack,” says Erni. Diffraction experiments at minus 196^oC — the condensation point of nitrogen — and high-resolution images at a low electron dose allowed the Empa scientists to eventually provide proof that the cross-linked molecules indeed exhibit a regular two-dimensional structure.

Potential application: a molecular sieve

The polymerization method that was developed is so gentle that all the monomer’s functional groups are also preserved at defined positions in the polymer. Says Sakamoto, “Our synthetically manufactured polymers are not conductive like graphene, but on the other hand we would be able to use them for example to filter the tiniest molecules.” In fact in the regularly arranged polymers there are small defined holes with a diameter in the sub-nanometer range. Moreover, tiny hexagons in the polymers, formed by benzene rings with three ester groups, can be removed by a simple hydrolytic process. This would form a “sieve” with an ordered structure suitable for the selective filtration of molecules.

However, before the researchers can think about practical applications, the task now is to characterize the material’s properties. First of all they must find a way to produce larger amounts and even larger sheet sizes. The size of the crystals is currently only 50 micrometers. Sakamoto stresses that “those, however, are already enormous degrees of polymerization at a molecular level.”

Science daily

For most people, that word means something malicious — shady criminals who listen in on private voicemails, or anonymous villains who cripple websites and break into email accounts.

For Facebook, though, “hacker” means something different. It’s an ideal that permeates the company’s culture. It explains the push to try new ideas (even if they fail), and to promote new products quickly (even if they’re imperfect). The hacker approach has made Facebook one of the world’s most valuable Internet companies.

Hackers “believe that something can always be better, and that nothing is ever complete,” Zuckerberg explains. “They just have to go fix it — often in the face of people who say it’s impossible or are content with the status quo.”

Zuckerberg penned those words in a 479-word essay called “The Hacker Way”, which he included in the document the company filed with government regulators about its plans for an initial public offering. The company is seeking $5 billion from investors in a deal that could value Facebook at as much as $100 billion.

The 27-year-old, who has a $28.4 billion stake in the stock deal, uses the H-word 12 times in the essay; “shareholder” appears just once. Should Zuckerberg have left those references out of his IPO manifesto, knowing full-well it could scare off potential investors? He could easily have described Facebook as “nimble” or “agile” instead.

“Symbolically, it doesn’t bode well to Facebook and to potential investors,” says Robert D’Ovidio, an associate professor of criminal justice at Drexel University in Philadelphia who studies computer crime. “I think it shows maybe an immaturity on his part. He should definitely know better.”

By using the word, Zuckerberg is also trying to reclaim it. To him, Steve Jobs and the founders of many of the world’s biggest technology companies were hackers.

“The word ‘hacker’ has an unfairly negative connotation from being portrayed in the media as people who break into computers,” Zuckerberg writes. “In reality, hacking just means building something quickly or testing the boundaries of what can be done.”

To be fair, the meaning has become complicated. Bad hackers destroy things with evil intentions. They break into the voicemails of crime victims and celebrities in search of a hot news story. They breach security systems to steal credit card data. Just this week, members of the loose-knit group Anonymous hacked into law enforcement websites around the world and gained access to information about government informants and other sensitive information.

Good hackers break things, too, sometimes. But they do it in the name of innovation. They call themselves “white hat” hackers to counter the criminal “black hats.” Often, they’re hired to expose security vulnerabilities at big corporations. Kevin Mitnick, who was convicted and sent to prison in the 1990s for computer hacking, now works as a security consultant. It’s the flip side of his past life, when he spent years stealing secrets from some of the world’s largest corporations.

“I break into computers to find holes before the bad guys do,” he says.

To Mitnick, Zuckerberg’s “Hacker Way” is about finding clever ways to fix problems. It can also mean identifying a new use for something old.

Nathan Hamblen, who works for the website Meetup.com, says the best hacks are those that do something unexpected, something surprising that no one else has thought of.

The term “hacking” dates back more than half a century, when geeks at the Massachusetts Institute of Technology were tweaking telephone systems and computers.

“MIT was the Mesopotamia of hacking. That’s where hacking culture began,” says Steven Levy, the Wired Magazine writer who authored the 1984 book “Hackers: Heroes of the Computer Revolution.”

The small community of hackers in the 1950s and ’60s judged one another on their creative and technical abilities, and wore the term as a badge of honor, says Levy, in much the same way that Zuckerberg does today.

“They were the ones who did what you weren’t supposed to do on a computer,” Levy explains.

Some were pranksters, too. In the 1970s, before they founded Apple, Steve Jobs and his buddy Steve Wozniak figured out how to break into telephone systems and make free phone calls. In one infamous prank, the two Steves dialed up the Vatican to find out who would pick up.

“Wozniak pretended to be Henry Kissinger wanting to speak to the pope. ‘Ve are at de summit meeting in Moscow, and we need to talk to the pope,’ Woz intoned. He was told that it was 5:30 a.m. and the pope was sleeping,” writes Walter Isaacson in his recent biography of Jobs.

It wasn’t until the 1980s and ’90s that hacking took a bad turn. Some blame Robert Morris, a computer science student who discovered a vulnerability in the Internet’s inner workings and unleashed the world’s first computer worm in 1988.

“He essentially brought the Internet to a grinding halt,” says D’Ovidio, the criminal justice professor. Morris was the first person charged under the federal Computer Fraud and Abuse Act that had been enacted two years earlier.

Then came movies like 1983′s “War Games,” which also fueled the public’s fear of hacking. In the film, a hacker unwittingly comes close to starting the next World War, thinking it’s all a computer game.

“It happened because of Hollywood and because there was no other word out there,” says Andrew Howard, 28, a research scientist at the Georgia Tech Research Institute. “Hacker is a cool word, right? It’s a neat-sounding word.”

The ’80s and ’90s were also a time when computers spread from geek circles to office cubicles and home desktops. They were becoming mainstream. But they were still mysterious to most people. They wondered: “How do they work? Is someone going to break into them?”

Zuckerberg’s hacker manifesto is a nod to Levy, who codified “The Hacker Ethic” in his book about the subculture. Among the principles: “Hackers should be judged by their hacking” and “Always yield to the hands-on imperative.”

The hands-on imperative is important to Facebook. Zuckerberg still spends hours writing computer code, even though he has hired hundreds of engineers.

That ethos helped Zuckerberg’s social network to prosper. As the once mighty MySpace stopped innovating, its users flocked to the cleaner, crisper, always-changing Facebook. News Corp. gave up on MySpace and sold it for $35 million last June. Meanwhile, Facebook’s user base ballooned to 845 million, even as the website has gone through changes and redesigns that have angered members and privacy advocates.

Zuckerberg and others may yet be able to clean up the term. Meetup’s Hamblen thinks it’s already happening.

“People aren’t as afraid of technology, which was driving the fear of hackers,” he says. “It was someone doing something with software that you don’t understand. As people become more comfortable with technology in general, then hacking becomes a way of seeing it as using it in a clever way.”

Technology companies, from the tiniest startups to those such as Facebook and online game maker Zynga, take the hacker ethic to heart. They host regular “hackathons,” where engineers pull caffeine-fueled all-nighters writing computer code, usually working together on projects that are not part of their day-to-day jobs. Some of Facebook’s biggest features, including chat, video and the new Timeline, came out of these hackathons, as Zuckerberg explained in the filing.

“Hackers believe that the best idea and implementation should always win — not the person who is best at lobbying for an idea or the person who manages the most people,” he writes.

This is the ethic that can lift fresh-faced college grads (or dropouts) to the highest echelons of the technology elite, or at least to a good job.

Cadir Lee, the chief technology officer at Zynga, the company behind the biggest games on Facebook, says he “absolutely” refers to himself as a hacker. Lee says, at Zynga the hacker way means being agile. It’s not the end of the world, say, if a game isn’t perfect when players first see it, or if it has a bug that needs to be fixed. Think of it as live TV, Lee suggests.

“The charm of ‘Saturday Night Live’ is that every once in a while you see a boom mic, or they forget their lines or crack up,” says Lee. “But it’s better to get something out there and entertain than to not have any show.”

source form: yahoo

The world’s biggest social network is expected to seek a $75 billion to $100 billion valuation in its IPO, the most anticipated stock offering from Silicon Valley since Google Inc went public in 2004.

At Granite Investment Advisors in New Hampshire, Chief Investment Officer Scott Schermerhorn has already been fielding queries from clients eager to get in on the action.

“We had some clients call and once we step them through the numbers, they sober up,” he said. “The valuation is 100 times earnings in a stock market that is trading at 12.”

“At the end of the day, if you have a small amount of money that you are in a position to lose a chunk of it and you want to speculate on Facebook, go ahead,” he added. “But don’t use money that you really need to save to do it. I would put it in Microsoft, which is dirt cheap right now.”

To be sure, most technology analysts would argue that Facebook’s growth potential far exceeds that of Microsoft Corp, whose stock has largely traded between $20 and $30 in the past decade. It is taking its first steps toward content streaming for instance, and has yet to make a serious overseas thrust.

And a $100 billion valuation for Facebook at the top end – while huge in absolute terms – is not that out of whack in Silicon Valley IPO tradition. Facebook is seeking a multiple of up to 27 times annual revenue, or up to 100 times earnings.

Apple Inc – today, the world’s most valuable technology corporation – went public at a valuation of just $1.19 billion in 1980, equivalent to 25 times revenue and 102 times earnings. Google – to which Facebook is most often measured against in terms of potential – was valued at $23 billion at the time of its 2004 debut, or 218 times earnings.

But the sheer size of Facebook’s valuation means that it will have to become the world’s first $700 billion company if it is to replicate the gain in Google’s stock.

“At these valuations, investors really need to set aside emotion…and invest with their heads,” said Edward Reinhart, managing partner at Capital Advisors Wealth Management, who owns Facebook shares bought on private markets two years ago.

Reinhart, who advises clients on retirement planning, warned that hype building up ahead of Facebook’s IPO could mean “dangerous waters for the retail investor.”

INSTITUTIONAL INVESTORS STOCK UP

Facebook, led by 27-year-old Mark Zuckerberg, on Wednesday filed its IPO prospectus with the Securities and Exchange Commission, seeking to raise $5 billion.

The anticipation surrounding the company and its growth potential recalls the hoopla that accompanied Apple’s, Google’s, and Amazon.com Inc’s stock debuts. All three companies have done the near-impossible — lived up to the hype.

There are many who believe Facebook will do the same, pointing to its 843 million users and the fact that the company is much bigger and more profitable than other recent Internet debuts, such as the loss-making Pandora Media Inc or Groupon Inc.

Social game company Zynga closed up nearly 17 percent on Thursday in the first trading session after Facebook revealed it made 12 percent of its revenue last year from the video game publisher.

“Facebook has the most potential,” said Greenwich, Connecticut-based investment manager Jeff Matthews, speaking about its business plan rather than its stock price. “It’s the next Google.”

While retail investors are still combing through the numbers and doing the math, institutional investors have quietly bought Facebook shares via private pre-IPO exchanges like SharesPost and SecondMarket.

About 50 equity funds of the 3,842 tracked by Morningstar disclosed holdings of Facebook stock, led by Morgan Stanley’s institutional Opportunity H fund with 3.5 percent of its $242 million portfolio devoted to the social network.

Other funds that have disclosed holdings included those managed by Fidelity, T. Rowe Price, ING, Principal and MassMutual.

EMOTIONAL CONNECTION

As with Apple and Google, consumers feel strong emotional connections to Facebook, which could make its stock vulnerable to wild swings if it attracts many retail investors.

When the SEC released Facebook’s IPO prospectus on Wednesday evening, its website slowed to a crawl as traffic increased 100 times. Facebook also made it into betting books – Irish bookmaker Paddy Power is taking bets on what the share price will be when the social network begins trading.

The odds are 7 to 2 so far that investors will be paying between $25 and $34.99 for a share, according to the bookmaker.

“The challenge is trying to keep individual investor enthusiasm in some sort of line with economic reality,” said Lise Buyer, an IPO adviser who worked at Google at the time of its IPO, but hasn’t worked on the Facebook IPO.

Facebook “has very strong prospects, but all companies have stock prices that at some point must correlate to fundamentals.”

The social network’s 2011 revenue rose 88 percent to $3.71 billion while net profit increased 65 percent to $1 billion in last year. Those are not stellar numbers when compared with Apple’s 65 percent growth in revenue to $108.24 billion in fiscal 2011. Apple also outpaced Facebook in terms of income growth, with profit increasing 85 percent to $25.92 billion.

Despite this, Apple – with nearly $100 billion in cash and securities – trades at a forward price-to-earnings ratio of 13 times, far lower than the 100 times historic P/E of Facebook’s IPO, assuming the $100 billion valuation.

Even Microsoft — which saw net income grow 23 percent to $23.1 billion and revenue rise 12 percent to 69.9 billion for fiscal 2011 — trades at 11 times future earnings.

That’s why Schermerhorn, whose firm already owns Apple shares, said he preferred to invest in Microsoft over Facebook. Amazon’s shares trade at a relatively dear forward P/E of 131, while Google trades at 19.5.

“I know it is dominant in its space. Granted, the space is not growing as quickly as Facebook, but I am getting a nice dividend to wait,” he said of Microsoft. “I don’t have that with Facebook.”

source form: yahoo

Under a memorandum of understanding, Artivision unit ArtiMedia Pte Ltd will incorporate its front-end in-video advertising platform and back-end advertisement serving technology into an Intel software development kit (SDK) that uses the U.S. semiconductor giant’s “Wi-Fi Direct” technology.

“A definitive agreement is expected to be entered into between Artimedia and Intel once the first working SDK with Artimedia’s front-end and back-end technology is deployed on a demo mobile device,” the Singapore firm said in a stock market filing.

Intel may also invest in Artivision if a definitive agreement is reached, the Singapore firm added.

source form: yahoo

Audience revealed details of its Apple partnership in January, when it filed paperwork for an initial public offering (IPO) of stock. Teardown work from iFixit and Chipworks revealed a dedicated Audience chip in the iPhone 4, but the iPhone 4S integrates Audience’s “EarSmart” technology directly into the A5 processor, the company’s S-1 filing said.

The details answered a question that Linley Group analyst Linley Gwennap had about the A5 chip that powers the iPhone 4S: why is it so big? Larger processors are more expensive and can consume more power, and chip designers strive to trim every last square millimeter from their designs.

“Even after accounting for the dual Cortex-A9 CPUs and the large GPU that provides the A5 with industry-leading 3D graphics performance, the remaining die area seems too large for the usual mundane housekeeping logic,” Gwennap said in a report yesterday. “To reduce system cost and eliminate the extra package required for the Audience chip, Apple cut a deal to integrate the noise-reduction technology directly into its A5 processor, which appears in the iPhone 4S.”

Audience also said in its filing that its iPhone 4-era technology was good only when the phone was held near the speaker’s mouth. Audience’s noise-reduction technology built into the iPhone 4S is better, though.

“This situation helps explain why Apple does not offer Siri as a software upgrade on the iPhone 4. Although the older phone includes an Audience chip, the company has since improved its technology to handle ‘far-field speech,’ which means holding the device at arm’s length rather than directly in front of the mouth,” Gwennap said.

Siri support has been a contentious issue for some owners of earlier iPhones. Hacks to bring Siri to older iPhones generally require technically complicated measures.

Audience said in its filing that its partnership to license its noise-reduction intellectual property (IP) began bearing fruit in the last quarter of 2011:

Commencing in the three months ended December 31, 2011, Apple has integrated our processor IP in certain of its mobile phones. Pursuant to our agreement, this OEM [original equipment manufacturer] will pay us a royalty, on a quarterly basis, for the use of our processor IP for all mobile phones in which it is used.

Audience’s second-generation technology, which introduced its far-field noise-reduction technology, began shipping in 2011, the company said in its filing. The iPhone 4 arrived in 2010, before far-field was included.

A third generation of Audience’s noise-reduction technology is on the way, too, and Apple is a licensee, though Audience cautioned that Apple isn’t contractually required to use it. Where it would likely be integrated is within the purported A6 expected to power the purported iPad 3.

“We have granted a similar license to this OEM for a new generation of processor IP; however, this OEM is not obligated to incorporate our processor IP into any of its current or future mobile devices,” Audience said.

A diagram of Audience’s technology for stripping out unwanted noise from an audio signal.

(Credit: Audience)

Apple isn’t the only customer, though it’s certainly the most prestigious. Other customers include HTC, LG, Pantech, Samsung, Sharp, and Sony, Audience said, for products such as Samsung’s Galaxy S II, HTC’s Titan, and Sony’s Tablet S.

The Apple partnership has been lucrative for Audience, though the company didn’t break out specific numbers.

“Foxconn, one of Apple’s CMs [contract manufacturers], accounted for 81 percent and 70 percent of our total revenue in 2010 and the nine months ended September 30, 2011, respectively,” Audience said. The 2010 revenue was $47.9 million, with a net income of $4.8 million, the company’s first profitable year. For the first three quarters of 2011 revenue was $79.7 million with net income of $13.9 million.

EarSmart uses a digital signal processor to try to remove background noise and secondary voices so phone calls sound better when people are in restaurants, trains, or other noisy environments.

“Imitating the complex processing that occurs from the inner ear to the brain, Audience’s intelligent EarSmart technology distinguishes and interprets sounds as people do naturally,” the company says of its technology. “In a mobile device, the earSmart processor effectively isolates and enhances the primary voice signal and suppresses surrounding noise–for both transmit and receive–to enable clear conversations nearly anywhere.”

Screening out noise gets harder when people are holding their phones farther from their mouths, as often happens while videoconferencing, making hands-free calls in a car, and issuing voice commands such as with the Siri system.

“Far-field uses are more vulnerable to background noise interference and poor voice quality given the speaker’s distance from the device,” Audience said.

In other words, without the latest Audience technology, Siri can’t hear you so well.

Audience’s noise-reduction technology is in several phones, including many from Samsung.

source form: cnet

Many will feel their lungs expand, therefore, on hearing that the New England Patriots’ quarterback and all-around perfect human being watched last year’s Super Bowl illegally on his laptop.

You might think I exaggerate, but no. The Associated Press heard him make the admissionquite casually in a Super Bowl news conference.

Surely the face of innocence.

(Credit: Screenshot: Chris Matyszczyk/CNET)

Here are his reported words: “Last year I was rehabbing my foot in Costa Rica, watching the game on an illegal Super Bowl Web site. And now I’m actually playing in the game. So, it’s pretty cool.”

There will be some who find it pretty cool, indeed, that Brady chose online illegality. Some feel that the NFL controls its broadcasts so much that, even when their home team is playing and they can’t get to the game, they cannot watch it on their local TV station if the game isn’t actually sold out.

Perhaps in anticipation–or even celebration–of Brady’s words, the authorities this week shut down 307 illegal sports streaming sites.

Still, one of the NFL’s most marketable stars seems to believe that watching illegal streaming sites is but normal behavior. This might encourage those who control sports to stream games in a more affordable and modern manner.

Because real sinners are sometimes driven to iniquity merely by the circumstances in which they find themselves and the parental figures who keep telling them “no.”

source form: cnet

One of the challenges facing many scientists in lesser-known fields is communicating what it is they work on. A contest aims to advance scientific research–while demystifying it for the general public–through visualizations.

The National Science Foundation and the journal Science announced the winners of the 2011 International Science and Engineering Visualization Challenge on Friday. “These winnerscommunicate science in a manner that not only captures your attention but in many instances also strives to look at different ways to solve scientific problems through their varied art forms,” said Monica Bradford, executive editor of Science, which is published by the American Association for the Advancement of Science (AAAS).

It’s the ninth year they’ve held the contest, which attracted entries from 33 countries and for the first time included a people’s choice award through online voting. The categories were Photography; Illustration; Informational Posters and Graphics; Interactive Games; and Videos.

With so much emerging technology research done at the microscopic scale or in the cosmos, visualizations help show the beauty in science and make the work of so many disciplines more accessible.

source form: cnet

The engineers, from the IBM T.J. Watson Research Center in Yorktown Heights, New York; ETH Zurich in Zurich, Switzerland; and Purdue University in West Lafayette, Indiana, have published their study on the first sub-10-nm CNT transistor in a recent issue of Nano Letters.

Many research groups are working on reducing the size of transistors in order to meet the requirements of future computing technology for smaller, denser integrated circuits. When today’s transistors (silicon metal-oxide-semiconductor field-effect transistors, or Si MOS-FETs) are shrunk, they lose their ability to effectively control electric current, a problem called short-channel effects. For this reason, researchers have been modifying the Si MOS-FET design in an attempt to make the transistor perform better at sub-10-nm gate lengths, but these devices still face performance challenges.

In the new study, the engineers have discarded silicon altogether and turned to single-walled CNTs. Due to their superior electrical properties and ultrathin (1-2-nm diameter) bodies, CNTs have been proposed as a replacement for silicon for several years. Their ultrathin bodies should allow CNTs to maintain gate control of the current in a transistor even at short channel lengths, potentially enabling them to avoid short-channel effects. The IBM team’s sub-10-nm CNT transistor is the first to demonstrate these advantages.

“The greatest significance of this work is in the demonstration that carbon nanotube transistors can not only perform well at sub-10-nm lengths, but that their performance is better than the best-reported Si-based transistors at similar lengths,” IBM researcher Aaron Franklin told PhysOrg.com. “For years it has been known that scaling bulk silicon devices would be extremely challenging, if not impossible, when lengths close in on 10-15 nm….The superb low voltage performance of this scaled carbon nanotube transistor is a sign post showing that there is a demonstrable alternative for extremely scaled transistors.”

Until the engineers built the sub-10-nm CNT transistor, no one knew that they would perform this well. Theories predicted that CNTs with ultrathin channels would experience a loss of gate control as well as a loss of drain current saturation in the output, both of which would degrade performance.

“The reason that theory projected a loss of gate control for nanotube transistors below 15 nm or so (despite their being extremely thin) is related to other unique transport physics for nanotube devices,” Franklin said. “Namely, the carrier effective masses (mass of electrons) are very small for nanotubes compared to other semiconductors, meaning they can tunnel or leak in the device more easily. This is one of the reasons that theories had suggested a loss of gate control, because these ‘light’ carriers would begin tunneling uncontrollably when the lengths became too small. In the paper, we show that the reason for this discrepancy is largely due to insufficient physics models for transport at the nanotube-metal contacts – previous models mostly ignore what could be happening with electrons getting through the metal-nanotube junction.”

When the engineers fabricated several individual transistors on the same nanotube, the smallest having a channel length of just 9 nm, they observed that the tiniest transistor exhibited superb switching behavior and drain current saturation, defying predictions. When compared to the best-performing sub-10-nm Si transistors of varying designs and diameters, the 9-nm CNT transistor had a diameter-normalized current density of more than four times that of the best silicon transistor. And it exhibited this impressive current density at a low operating voltage (0.5 volts), which is important for reducing power consumption.

The researchers predict that theoretical models can be improved by focusing more on the transport between the metal contacts and CNT. They also think that the high-performing 9-nm CNT transistors demonstrate the potential for using CNT transistors in tomorrow’s computing technology.

“The chief implication is that carbon nanotubes are still worth consideration for a future scaled transistor technology,” Franklin said. “What is often not realized by those outside the field is that carbon nanotube transistors are essentially the only non-silicon devices that have experimentally been shown to have promise in extremely scaled transistors. There are many devices promoted by theory, or demonstrated in larger device structures, but none have been able to show the level of research bench-top performance that nanotubes have. Now, that said, it should be noted that there are challenges ahead before anyone will see an integrated transistor solution from nanotubes. But, to date, nothing related to nanotube transistors has been shown to be fundamentally impossible to solve, from placement of nanotubes in precise locations to the complete separation of metallic and semiconducting nanotubes.”

source form: physorg