Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Chemists adapt casting technique to make ordered nanocarbons

11.05.2005


Technique could revolutionize nanoelectronics manufacturing



Carnegie Mellon University scientists have harnessed an experimental technology to produce polymer films with long-range-ordered nanostructure and easily convert them into highly ordered "nanocarbon arrays." Called zone casting, this technology could revolutionize the way industrial nanoelectronic components are made. The research findings are in press with the Journal of the American Chemical Society. "We’ve found that zone casting produces highly organized polymer films that could serve as templates for creating ordered nanopatterns with other materials," said Tomasz Kowalewski, an assistant professor of chemistry who is leading the Carnegie Mellon team. "The technique could, for example, help produce data storage arrays with increased density and reliability." Kowalewski also expects that zone casting could produce materials for other nanoelectronic devices, like field emission arrays.

To create long-range-ordered films, Kowalewski’s team used "block copolymers," which are made of long-chain molecules with distinct "blocks" of chemically different repeating units. To create self-assembling nanostructures from block copolymers, Kowalewski used molecules with blocks that naturally repel one another, like oil and water. Such copolymer strands spontaneously assume energetically favorable structures, like balls, cylinders or sheets.


In recent years, scientists and engineers have sought to use these unusual structures in electronics and data storage settings. In the latter case, thin block copolymer films are used as lithographic masks to pattern ultra-high density data storage media. However, nanostructures spontaneously formed by block copolymers usually lack long-range order necessary for such applications. Thus, numerous labs are pursuing various strategies to encourage block copolymers into ordering themselves over a large scale.

"Zone casting appears to be particularly well-suited to achieve this goal with a variety of block copolymers," Kowalewski said. In zone casting, a nozzle ejects a solution onto an advancing surface, or moving support. By modifying the temperature, the speed of the advancing surface and other factors, researchers already have been able to control the alignment and solidification of molecular crystals used to make organic electronic devices. The zone-casting technique was originally developed by scientists from the Polish Academy of Sciences.

The Carnegie Mellon team hypothesized that a similar approach also could help establish and control long-range order of block copolymer domains. Using this technique, doctoral student Chuanbing Tang produced thin films of block copolymers made of polyacrylonitrile (PAN) and poly(n-butyl acrylate) (PBA) on a moving chip. The films consisted of alternating layers of PAN and PBA, and these layers were oriented perpendicular to the surface and to the direction of the advancing chip. Then, using a method developed earlier in the Kowalewski lab, Tang used a high-temperature treatment to convert the long-range-ordered polymer films into nanostructured carbon, while remarkably preserving the long-range order.

"Zone casting offers the perfect way to direct higher order assembly so that we can pre-organize carbon precursor structures," Kowalewski said. "More important, our ongoing work indicates that we will be able to use it with other copolymer systems, forming different structures, such as hexagonally packed arrays of vertical cylinders."

These latter systems are of particular interest as masks for lithographic patterning of magnetic materials for data storage arrays. The research was supported by the National Science Foundation and the Controlled Radical Polymerization Consortium at Carnegie Mellon.

Lauren Ward | EurekAlert!
Further information:
http://www.cmu.edu

More articles from Power and Electrical Engineering:

nachricht Did you know that the wrapping of Easter eggs benefits from specialty light sources?
13.04.2017 | Heraeus Noblelight GmbH

nachricht To e-, or not to e-, the question for the exotic 'Si-III' phase of silicon
05.04.2017 | Carnegie Institution for Science

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>