Electronics - Page 35

Researchers from Rice University and the Oak Ridge National Laboratory (ORNL) found a new method to control the growth of uniform atomic layers of molybdenum disulfide (MDS), a semiconductor together with graphene can be used to make 2D electronic devices. Unlike graphene, MDS has a band gap.

The researchers goal is to create large MDS sheets (using CVD) and then use it together with graphene and the insulator hexagonal boron nitride (hBN) to form field-effect transistors, integrated logic circuits, photodetectors and flexible optoelectronics. MD5 isn't flat - it's actually a stack, with a layer of molybdenum atoms between two layers of sulfur atoms. It's a challenge to actually bind these three materials together.

Researchers from Korea's Ulsan National Institute of Science and Technology (UNIST) managed to embed a LED inside a regular soft contact lens, using transparent and conductive electrodes made from graphene and silver nanowires. This is the first time an electronic device was embedded inside a contact lens using flexible and transparent materials.

The researchers final goal is to develop wearable computer displays inside contact lenses. Basically it will be like a Google Glass HMD, but without any external display components. Obviously that goal is still far in the future: currently they manged to embed just one LED and not a full display.

Researchers from Korea's Sungkyunkwan University developed a highly flexible and transparent memory device using graphene electrodes (both and anode and the cathode). This is the first time graphene is used for the bottom electrode in such a device, and this was achieved by using a chemical union of the bottom electrode with the molecular film of organic molecules (which is placed between the two electrodes).

This is not the first graphene based flexible memory device. In October 2012 researchers from Rice University developed highly transparent (95%), flexible, nonvolatile resistive memory devices based on silicon oxide (SiOx) and graphene. In March 2013 Researchers from EPFL designed a new flexible, small and fast flash memory cell prototype from graphene and Molybdenite (MoS2).

Researchers from Northwestern University developed a new approach for inkjet printed graphene inks (made from graphene flakes). The new process does not leave any residues on the graphene, and it also produces a graphene ink with a low number of flake-to-flake junctions. This results in highly conductive ink.

The process uses ethanol as a solvent and ethyl cellulose as a stabilizing polymer. The outcome of this is a 15% graphene black powder. The graphene flakes are 50x50 nm² in size. This powder is then dispersed into a solvent and this creates a fluid ink. The researchers demonstrated inkjet printing - which can be used to make precise patterns, and even multiple-layer structures.

The UK's Engineering and Physical Sciences Research Council (EPSRC) awarded the University of Nottingham with £1.3 million (just over $2 million) that will be used to buy a new molecular beam epitaxy (MBE) system. This new system will enable the growth of high quality, large area layers of graphene and boron nitride.

Researchers from the University plan to study new materials based on graphene and boron nitride for electronic and optoelectronic applications.

Researchers from the University of Illinois discovered that when InGaAs nanowires are grown on graphene, they self-assemble into an unexpected structure, in which the indium arsenide (InAs) acts as a core with an InGaAs shell around it. This structure may be very useful for electronics applications.

The researchers wanted to try graphene as a substrate because silicon (which is most commonly used) is expensive, thick and brittle. Graphene is a lot thinner, and it's flexible, too. Now it turns out that grapheen also offers new, unexpected functionality. And the fact that this structure was built spontaneously is very good, too as it makes it easy to construct such nanowires.

Bluestone Global Tech (BGT) was founded in 2011 in New York with an aim to produce graphene. The company offers high-quality, fully customizable graphene on several substrates (Quartz, Copper, Silicon and others). BGT's CEO, Dr. Chung Ping Lai, was kind enough to answer a few questions we had about the company's business and technology.

Dr. Lai became BGT's CEO in November 2012. Previously he worked with Taiwan's ITRI institute, Veeco, Applied films and other companies. Dr. Lai received his Ph.D. degree from the Department of Ceramics Science and Engineering of Rutgers University in 1992. 

Researchers from Spain's UPC and Georgia Tech have been granted $120,000 from Samsung to develop graphene based micrometer-scale highs-peed short-distance antennas. This project (called Graphene-Enabled Wireless Communication, or GEWC). These antennas could radiate electromagnetic waves in the terahertz band and would allow for high-speed information transmission. These antennas will be a thousand times smaller than what can be made with current technology.

The first application will probably be high-speed communication inside a single device - for example between the CPU and the memory, or between cores in multi-core processors. In fact the researchers say that this technology could lead to processor with thousands of "sub processors".

Researchers from the University of Manchester discovered that sandwiching graphene between boron nitride layers can produce highly-accurate capacitors. Such capacitors could be cheaper and easier to fabricate compared to traditional transistors.

The researchers used quantum capacitance spectroscopy to investigate the exceptional properties of graphene, as this measurements shows better accuracy.

The University of Cambridge announce plans to establish a new center for graphene research. The Cambridge Graphene Centre (CGC) will start operation on February 1st 2013 and the university will open a dedicated facility with state-of-the-art equipment towards the end of 2013.

The UK government gave a grant of over £12 million to support the new center's activities. The CGC will use the money to buy equipment and support projects that aim to develop new mass-production high-quality graphene production processes and some potential applications. The CGC's director will be Professor Andrea Ferrari.