Northwestern Univ. and Argonne National Laboratory scientists have recently overcome problems with growing graphene on chemically inert substrates, demonstrating the first growth of graphene on a single-crystal silver substrate. Their method could advance graphene-based optical devices and enable the interfacing of graphene with other two-dimensional materials.
Researchers in Germany are showing the way toward low-cost, industrial-scale...
By coating compact disks in photocatalytic compounds and spinning them to clean water...
A new method developed in Germany makes it possible to manufacture ultra-thin saw wires by placing diamond on carbon nanotubes. The new invention is designed to cut through silicon wafers with minimum kerf, or “sawdust”, loss that is the unavoidable result of current tools used in semiconductor wafer fabrication.
An international group of researchers from the U.S. and South Korea have discovered a groundbreaking technique in manufacturing nanostructures that has the potential to make electrical and optical devices smaller. The new patterning technology, called atomic layer lithography, based on a layering technique at the atomic level and relies on a surprising low-tech tool: Scotch Magic tape.
Engineers at NIST have developed a new technique for fabricating high aspect ratio 3-D nanostructures over large device areas using a combination of electron beam lithography, photolithography and resist spray coating. While it has long been possible to make complicated 3-D structures with many mask layers or expensive grayscale masks, the new technique enables researchers to etch features in two process steps without masks
In the future, carbon nanomembranes are expected to be able to filter out very fine material or even gases. Right now, basic research is concentrating on methods for the production of these nanomembranes. Using a new process a research team in Germany has produced 12 different carbon nanomembranes from a variety of starting materials.
Scientists at Switzerland have developed a new method for making antimicrobial surfaces that can eliminate bacteria under a minute. The breakthrough relies on a new sputtering technique that uses a highly ionized plasma to, for the first time, deposit antibacterial titanium oxide and copper films on 3-D polyester surfaces. This promotes the production of free radicals, which are powerful natural bactericides.
Flexible thin film solar cells that can be produced by roll-to-roll manufacturing are a highly promising route to cheap solar electricity. Researchers in Switzerland report that they have designed a low-cost cadmium telluride solar cell technology based on metal foil substrates. By doping the cells with cooper, they have elevated efficiency from 8 to 11.5%.
Electron beam (e-beam) lithography enables researchers to write very small patterns on large substrates with a high level of precision. In the Nano3 cleanroom facility at the Univ. of California, San Diego’s Qualcomm Institute, a new Vistec e-beam writer is helping to develop nanoscale transistors for integrated electronics, as well as neural probes for brain diagnostics.
Diffusion of sodium ions from the glass substrate is thought to be the primary cause of potential-induced degradation (PID) in crystalline silicon photovoltaic cells. A research institute and metals company in Japan have partnered to develop a thin film solution. The titanium oxide-based composite metal compound they have developed is inexpensive to produce and highly scalable.
Concentric hexagons of graphene grown in a furnace at Rice University represent the first time anyone has synthesized graphene nanoribbons on metal from the bottom up—atom by atom. As seen under a microscope, the layers brought onions to mind. Though flat graphene could never be like an onion, the name stuck.
A team led by John Hagopian, an optics engineer at NASA’s Goddard Space Flight Center, has recently demonstrated that it can grow a uniform layer of carbon nanotubes through the use of atomic layer deposition. The marriage of the two technologies now means that NASA can grow nanotubes on 3-D components, such as complex baffles and tubes commonly used in optical instruments.
A polymer thin film solar cell (PSC) produces electricity from sunlight by the photovoltaic effect. Though light and inexpensive, PSCs currently suffer from a lack of enough efficiency for large scale applications and they also have stability problems. Researches in Korea have designed and added multi-positional silica-coated silver nanoparticles that have greatly improved stability and performance of these cells.
Twenty years after the discovery of single-walled carbon nanotubes (SWNTs), a team of scientists in Finland, Russia, and Denmark has managed to control chirality in carbon nanotubes during their chemical vapor deposition synthesis. Because chirality defines the optical and electronic properties of nanotubes, the ability to predict it has been a longstanding goal for materials developers.
Wake Forest University's Organic Electronics group has developed an organic semiconductor “spray paint” that can be applied to large surface areas without losing electric conductivity. The new spray-deposition method has the advantages of drop casting, spin coating, and prior spray-on techniques: It can applied to large surfaces of any medium, retaining electrical performance.
Until recently, there has been no systematic way of evaluating how different anti-fog coatings perform under real-world conditions. A team of MIT researchers has developed such a testing method, and used it to find a coating that outperforms others not only in preventing foggy buildups, but also in maintaining good optical properties without distortion.
A team led by Oxford University scientists in the U.K., has overcome a key problem of growing graphene—a one atom-thick layer of carbon—when using chemical vapor deposition. The tiny flakes of graphene typically form with random orientations, leaving defects or 'seams' between flakes that grow together. A combination of pressure a simple copper foil can remove these defects.
Researchers at the Aalto University School of Chemical Technology have applied atomic layer deposition (ALD) technique to the synthesis of thermoelectric materials. Converting waste energy into electricity, these materials are a promising means of producing energy cost-effectively and without carbon dioxide emissions in the future.
Conventional sterilization techniques based on a blast of radiation, or exposure to toxic gas, can damage the functional biological components of certain medical devices. According to a team of researchers from Germany and Austria, materials containing an extract from licorice can be used to sterilize and protect medical devices and implants which include biological components.
New technologies in microelectronics and lithography typically require the presence of nanoscale polymer films in contact with a substrate. Successful engineering of these structures requires an understanding of the interplay between the dynamics of the thin film and the underlying substrate, and recent experiments at the Argonne National Laboratory’s Advanced Photon Source have produced new insights into these compositions.
Within optical microchips, light finds its way through waveguides made of silicon, and is amplified with the help of other semiconductors, such as gallium arsenide and erbium. But until recent work in The Netherlands, no chip existed on which both silicon and erbium-doped material had been successfully integrated. The new chip now amplifies light up to 170 Gbit/sec.
Scientists at the Norwegian University of Science and Technology report they have patented and are commercializing gallium arsenide (GaAs) nanowires grown on graphene. These semiconductors, which are being developed for market by the the company CrayoNano, are grown on atomically-thin graphene using molecular beam epitaxy.
Engineers at Cornell University have invented a way to pattern single atom films of graphene and boron nitride, an insulator, without the use of a silicon substrate. The technique, called patterned regrowth, is reliant on conventional silicon photolithography technology and could lead to substrate-free circuits that would be atomically thin yet retain high tensile strength and superior electrical performance.
Flat panel displays and mobile phones require thin, efficient, and low-cost light emitters, which are typically made from pixels wired to complex electronic circuits. Engineers in Singapore have now developed a display technology that requires a much simpler architecture: a thin perforated gold film with a liquid crystal layer.
Vivek Dwivedi, a technologist at NASA's Goddard Space Flight Center is experimenting with an emerging technology that might provide an effective technique for defending sensitive spacecraft components from the high-velocity bombardments. Using atomic layer deposition, he is applying a new super-strong, ultra-thin coating made of tiny tubes of boron nitride, similar in appearance to the bristles on a toothbrush.
A group of Massachusetts Institute of Technology engineers has discovered a way of making perfectly ordered and repeatable surfaces with patterns of microscale wrinkles. The method involves chemical vapor deposition of a layer onto a stretched silicon-polymer substrate. When tension is released first one way, then the other, a perfectly ordered wrinkled pattern emerges.
Biofilms stick to just about everything, from copper pipes to steel ship hulls to glass catheters, and can be both a nuisance and a health threat. A team of Harvard University scientists has developed a slick 99%-effective way to prevent the troublesome bacterial communities from ever forming on a surface.
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