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South Korean researchers have recently made a flexible nonvolatile memory based on memristors—fundamental electronic circuit elements discovered in 2008—using thin graphene oxide films. Memristors promise a new type of dense, cheap, and low-power memory and have typically been made using metal oxide thin films. The new graphene oxide devices should be cheaper and simpler to fabricate—they could be printed on rolls of plastic sheets and used in plastic RFID tags or in the wearable electronics of the future. "We think graphene oxide can be a good candidate for next-generation memory," says Sung-Yool Choi, who leads flexible devices research at the Electronics and Telecommunications Research Institute in Daejeon, South Korea. Choi and his colleagues reported their device last week in Nano Letters.

Clearly the most attractive super hero power for nanotechnology at the moment is invisibility. Last month we had a nano-enabled coating that managed to make aircraft invisible to radar. Now we have a metamaterial consisting of fishnet-like film containing holes about 100 nanometers in diameter that could serve as an invisibility cloak. While I personally might be persuaded to choose Spider-like climbing abilities for my nano-enabled super hero power, invisibility does pose an attractive option. However, invisibility is far from the point of this research conducted at the Birck Nanotechnology Center, Purdue University and appears in the August 5th edition of the journal Nature.

The other day I was critical of the UK’s nanotechnology strategy document. However, I am a great admirer of the UK scientists and engineers working in the field of nanotechnology, which makes the recent strategy document such a double disappointment. To sort of atone for my criticism, I wanted to highlight a UK-based researcher, Professor Philip Moriarty at the University of Nottingham, who first came to my attention a few years back on the pages of Richard Jones’ blog Soft Machines , when Moriarty had organized a debate on the subject of radical nanotechnology, otherwise known as molecular nanotechnology. I also recently noted his ability to secure funding for his research to test the theories of molecular manufacturing, and wondered if he can do it why aren’t more molecular manufacturing theorists doing it.

Tiny semiconductor dots could lead to a new type of circuit based on magnetism rather than current flow. At least that’s the hope of researchers who’ve made the dots and are hoping to build them into a workable device. ”We want to make it into a so-called nonvolatile transistor,” says Kang Wang, head of the Device Research Laboratory at the University of California, Los Angeles. Such a ”spintronic” transistor would retain its logic state in the absence of current and require less power to switch a bit, reducing the electrical power required by a computer chip by as much as 99 percent. Wang’s research, supported in part by Intel, was published in March in the online version of Nature Materials. Where electronic transistors rely on the presence or absence of current to register the ones and zeros of digital logic, spintronic transistors depend on ”spin,” a quantum characteristic of the electron. Picture the electron as a rotating globe. When the north pole is pointing upward, that’s spin up; when pointing the other way, it’s spin down. When the spins of most electrons are aligned, the material is magnetic. When their spins are random, the material isn’t. An applied current can align or randomize the spins, allowing for spin-based switches.

Their new research is published in the online edition of the Proceedings of the National Academy of Sciences (PNAS), and will soon be published in the print edition of the journal. The findings may enable new applications for semiconductors --materials that are the foundation of today's information technology. In particular, they may help identify alternative materials to use for building a potential quantum computer.

Researchers at Purdue University have developed a new design employing carbon nanotubes and small copper spheres that wicks water passively towards hot electronics that could meet the challenges brought on by increasing frequency speeds in chips. The problem of overheating electronics is well-documented and in the past the issue has been addressed with bigger and bigger fans. But with chip features shrinking below 50 nanometers the fan solution is just not cutting it. The Purdue researchers, led by Suresh V. Garimella, came up with a design that uses water as the coolant liquid and transfers the water to an ultrathin thermal ground plane. The design naturally pushes the water through obviating the need for a pump and through the use of microfluidic design is able to boil the water fully, which allows the wicking away of more heat.

Ever since graphene was first produced in a lab at the University of Manchester in 2004, researchers around the world have been fascinated with its potential in electronics applications. Graphene possessed all the benefits of carbon nanotubes (CNTs), namely its charged-carrier mobility, but it didn’t have any of the down sides, such as CNTs’ need for different processing techniques than silicon and the intrinsic difficulty of creating interconnects for CNTs. But all was not easy for applying graphene to electronics applications. One of the fundamental problems for graphene was its lack of a band gap, which left it with a very low on-off ratio measured at about 10 as compared to in the 100s for silicon. Now this fundamental hurdle has been overcome. Based on research led by Phaedon Avouris at IBM’s IBM T.J. Watson Research Center, Yorktown Heights, New York, IBM is reporting that they have created a significant band gap in graphene.

4 January 2010—Though flexible devices such as roll-up displays have been promised for several years, their commercialization has been stalled by a missing ingredient: a flexible form of flash memory. But researchers at the University of Tokyo have recently developed an organic, floating-gate nonvolatile memory that behaves like flash memory, which may solve that problem. While silicon-based flash memory is fine for the mass data storage found in cellphones, digital music players, and thumb drives, fabricating it requires high processing temperatures, thus ruling out its production on flexible substrates like plastic. Organic semiconductors, however, can be processed at temperatures well below the melting point of most plastics. What's more, "the cost of flash memory is too high to use in applications that require large arrays of memory," says Tsuyoshi Sekitani, an assistant professor in the University of Tokyo's department of electrical and electronic engineering and one of the researchers who developed the new memory. "But we can print our organic memory on flexible substrates and over large areas using inkjet printers. So costs will be low."

Three-dimensional microchip designs are making their way to market to help pack more transistors on a chip as traditional scaling slows down. By stacking logic chips on top of one another other or combining logic chips with memory or RF with logic, chipmakers hope to sidestep Moore's Law, increasing the functionality of smartphones and other gadgets not by shrinking a chip's transistors but the distance between them. "There's a big demand for smaller packages in the consumer market, especially for the footprint of a mobile phone, or for improving the memory bandwidth of your GPU," says Pol Marchal, a principal scientist of 3-D integration at European microelectronics R&D center Imec. On 9 February, at the IEEE International Solid-State Circuits Conference (ISSCC), in San Francisco, Imec engineers presented some key design challenges facing 3-D chips made by stacking layers of silicon circuits using vertical copper interconnects called through-silicon vias (TSVs). These design constraints will have to be dealt with before TSVs can be widely used in advanced microchip architectures, Marchal says.

The moving parts of micromechanical machines tend to seize up under the forces of sticking and friction that engineers call stiction. The problem yields to solid lubricants, notably graphite (sheets of carbon atoms called graphene stacked in layers), although for a long time no one understood exactly why this happens. Now nanotechnology researchers, led by Professor Robert Carpick at the University of Pennsylvania and Professor James Hone at Columbia University, in New York City, have shown that how effective the lubrication is depends on the number of layers of graphene in the graphite. In particular, more layers means better lubrication. Because the same relationship between layers and lubrication occurs in thin sheets of molybdenum disulfide, niobium diselenide, and boron nitride—materials of widely differing properties—the workers conclude that this behavior is a fundamental aspect of friction. They expect that the discovery will lead to better lubrication of tiny moving parts. The researchers published details of their experiments in a recent issue of Science.

One of the biggest commercial applications of spintronics in computing to date has been the use of giant magnetoresistance (GMR), the material phenomenon that makes possible the huge storage capacity of today’s hard disk drives. In the awarding of the 2007 Nobel Prize in Physics, GMR was cited as the first big commercial application for nanotechnology. But extending the commercial application of spintronic-enabled systems beyond read heads for HDDs has proven to be a difficult task. One need only look at the seemingly endless travails of NVE Corporation, which in its financial results still shows it greatest revenue growth in contract research as opposed to product sales. While recent research from a team of researchers at Ohio State University and the University of Hamburg in Germany may not turn around the fortunes of spintronics in the short term, it does provide a way to better characterize the spin of electrons and thereby promises better ways of exploiting it for electronics applications. The researchers are reporting in Nature Nanotechnology that they have for the first time been able to create images of the spin direction of electrons.

With the introduction of the WEBENCH Online Design Environment in 1999, National Semiconductor made it possible for design engineers to create a reliable power supply circuit over the internet in minutes. The user specified the circuit performance and the WEBENCH Toolset delivered. Today, WEBENCH Designer creates and presents all of the possible power, lighting, or sensing circuits that meet a design requirement in seconds. This enables the user to make value based comparisons at a system and supply chain level before a design is committed. This expert analysis is not possible anywhere else.

A test circuit built with nanowires of silicon could point the way to much smaller transistors, say the IBM researchers who created it. Researchers from IBM’s Thomas J. Watson Research Center announced today at the annual Symposium on VLSI Technology, in Honolulu, that they have built a ring oscillator out of field-effect transistors (FETs) based on nanowires with diameters as small as 3 nanometers. The oscillator—is composed of 25 inverters using negative- and positive-channel FETs. The device, which demonstrated a delay of just 10 picoseconds per stage, shows that engineers can build a working circuit from transistors with much shorter channel lengths than today’s devices. Current flows through an FET’s channel under the control of the device’s gate. Scaling down the channel length will be critical if the dimensions of circuits on silicon chips are to continue to shrink, says Jeffrey Sleight, a senior technical staff member at IBM.

Given the maturity of MOSFETs, selecting one for your next design may seem deceptively simple. Engineers are familiar with the figures of merit on a MOSFET data sheet. Selecting a MOSFET requires the engineer to use their expertise in scrutinizing different specifications for individual applications. In an application such as a load switch in a server power supply, the switching aspects of a MOSFET matter little because the MOSFET is on almost 100% of the time. The on resistance (RDS(ON)) may be the key figure of merit in such an application. Still other applications, including switching power supplies, use MOSFETs as active switches, and cause the engineer to value other MOSFET performance parameters. Let us consider some applications and their prioritization of MOSFET specifications.

Recent advances in the size and performance of FPGAs, coupled with advantages in time-to-market, field-reconfigurability and lower up-front costs, make FPGAs ideally suited to a wide range of commercial and defense applications [6]. In addition, FPGAs generality and reconfigurability provide important protections against the introduction of Trojan horses during semiconductor manufacturing process[8]. As a result, FPGA applications increasingly involve highly-sensitive intellectual property and trade-secrets, as well as cryptographic keys and algorithms [7].

No, we're not talking about a Wonder Woman-type of invisible plane, but rather one that becomes very difficult to detect with radar. The Israel-based Ynetnews is reporting that an Israeli company called Nanoflight has successfully run a test on dummy missiles that were painted with the nano-enabled coating and have shown that radar could not pick them up as missiles.

Last week, Nanowerk’s Spotlight piece covered recent research in which Swiss researchers demonstrated that they could remove metal ions, steroid drugs and proteins from blood by using nanomagnets. The nanomagnets are basically carbon-coated iron carbide at the nanoscale (an average diameter of 30 nanometers) and are functionalized with linker molecules that attract the target material in the blood.

IBM's light-powered links overcome the greatest speed bump in supercomputing: interconnect bandwidth

Not so long ago, artists routinely made their own paints using all sorts of odd ingredients: clay, linseed oil, ground-up insects—whatever worked. It was a crude and rather ad hoc process, but the results were used to create some of the greatest paintings in the world. Today I and other scientists are developing our own special paints. We’re not trying to compete with Vermeer or Gauguin, though. We hope to create masterpieces of a more technical nature: optoelectronic components that will make for better photovoltaic cells, imaging sensors, and optical communications equipment. And we’re not mixing and matching ingredients quite so haphazardly. Instead, we’re using our blossoming understanding of the world of nanomaterials to design the constituents of our paints at the molecular level.