Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Nanomaterials: Formation in a flash - A new lithography technique enables the production of nanoscale patterns of titania for high-tech applications

The nanoscale titania pattern before and after heat-treatment.  2012 American Chemical Society
The nanoscale titania pattern before and after heat-treatment.

2012 American Chemical Society

Abstract:
Titanium dioxide, or titania, is an inorganic material commonly used as a whitening agent in food and toothpaste. It is also used as one of the main active ingredients in sunscreens. The properties that make titania useful in commercial applications namely its whitening ability and high refractive index are now being exploited in a wide range of technological applications.

Nanomaterials: Formation in a flash - A new lithography technique enables the production of nanoscale patterns of titania for high-tech applications

Singapore | Posted on July 6th, 2012

One particular area of interest has been the application of titania in dye-sensitized solar cells devices that can be used to convert sunlight into electricity. Such application often requires the formation of intricate surface patterns, with the key limiting factors for development being cost and speed of processing. Now, Ramakrishnan Ganesan, Mohammad Saifullah and co-workers at the A*STAR Institute of Materials Research and Engineering have described the use of a technique called step-and-flash imprint lithography (SFIL) to produce such patterns on the nanoscale.

"The precursor method to SFIL is thermal nanoimprint lithography, which is extremely time-consuming as it requires temperature-cycling processes to form a pattern," explains Saifullah. "A mold could be pressed into a heated (and softened) resist material or a liquid precursor could be forced into a mold and then hardened upon heating."

Newer processes eliminate the need for heating by using irradiation with ultraviolet (UV) light to harden the polymer. Although this process may be ideal for organic polymer materials, it is more problematic when using inorganic materials such as titania as the liquid precursor materials are highly viscous and do not spread easily. As a result, the dispensing nozzle may sometimes become blocked.

The chemicals used to make titania can also be unstable in solution, so the team had to identify a mixture of components that offered a combination of stability and low viscosity. "We found that an allyl functionalized titanium complex was stable in combination with other polymer precursors," explains Saifullah. The final component of the mixture is a photoinitiator which starts the polymerization process upon irradiation with UV light.

The mixture was dispensed onto the surface in the form of droplets, and the mold pressed into place to help the liquid spread. Irradiation with UV light results in hardening of the pattern, after which the mold can be removed. A final heating step burns away the organic material, leaving behind a shrunken version of the original pattern made from titania (see image). Significantly, the aspect ratio of the pattern is maintained after the heat-treatment process.

"Our current method is quite specific to titania, but after tackling this most important material, we hope to develop similar procedures for other inorganic materials," says Saifullah.

The A*STAR-affiliated researchers contributing to this research are from the Institute of Materials Research and Engineering

References:

Ganesan, R. et al. Direct patterning of TiO2 using step-and-flash imprint lithography. ACS Nano 6, 1494-1502 (2012). (Direct link to article below)

####

For more information, please click here

Contacts:
A*STAR Research

Copyright © Agency for Science, Technology and Research (A*STAR)

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Agency for Science, Technology and Research (A*STAR):

Institute of Materials Research and Engineering:

Link to original article in ACS Nano:

Related News Press

News and information

Carbon nanotube optics poised to provide pathway to optical-based quantum cryptography and quantum computing: Researchers are exploring enhanced potential of carbon nanotubes for unique applications June 18th, 2018

Camouflaged nanoparticles used to deliver killer protein to cancer June 17th, 2018

Squeezing light at the nanoscale: Ultra-confined light could detect harmful molecules June 17th, 2018

Physicists devise method to reveal how light affects materials: The new method adds to the understanding of the fundamental laws governing the interaction of electrons and light June 15th, 2018

Chemistry

Quantum Interference May Be Key to Smaller Insulators: Breakthrough could jumpstart further miniaturization of transistors June 6th, 2018

Density gradient ultracentrifugation for colloidal nanostructures separation and investigation June 5th, 2018

From Face Recognition to Phase Recognition: Neural Network Captures Atomic-Scale Rearrangements: Scientists use approach analogous to facial-recognition technology to track atomic-scale rearrangements relevant to phase changes, catalytic reactions, and more May 31st, 2018

Northwestern researchers predict materials to stabilize record-high capacity lithium-ion battery: Advancement could pave the way for less expensive, longer-lasting batteries for electric vehicles May 29th, 2018

Discoveries

Carbon nanotube optics poised to provide pathway to optical-based quantum cryptography and quantum computing: Researchers are exploring enhanced potential of carbon nanotubes for unique applications June 18th, 2018

Camouflaged nanoparticles used to deliver killer protein to cancer June 17th, 2018

Squeezing light at the nanoscale: Ultra-confined light could detect harmful molecules June 17th, 2018

Physicists devise method to reveal how light affects materials: The new method adds to the understanding of the fundamental laws governing the interaction of electrons and light June 15th, 2018

Announcements

Carbon nanotube optics poised to provide pathway to optical-based quantum cryptography and quantum computing: Researchers are exploring enhanced potential of carbon nanotubes for unique applications June 18th, 2018

Camouflaged nanoparticles used to deliver killer protein to cancer June 17th, 2018

Squeezing light at the nanoscale: Ultra-confined light could detect harmful molecules June 17th, 2018

Physicists devise method to reveal how light affects materials: The new method adds to the understanding of the fundamental laws governing the interaction of electrons and light June 15th, 2018

Energy

Physicists devise method to reveal how light affects materials: The new method adds to the understanding of the fundamental laws governing the interaction of electrons and light June 15th, 2018

Tripling the Energy Storage of Lithium-Ion Batteries: Scientists have synthesized a new cathode material from iron fluoride that surpasses the capacity limits of traditional lithium-ion batteries June 14th, 2018

Remote control of transport through nanopores: New study outlines key factors affecting the transfer of molecules through biological channels May 24th, 2018

Team achieves two-electron chemical reactions using light energy, gold May 15th, 2018

Solar/Photovoltaic

Team achieves two-electron chemical reactions using light energy, gold May 15th, 2018

Hematene joins parade of new 2D materials: Rice University-led team extracts 3-atom-thick sheets from common iron oxide May 8th, 2018

Harvesting clean hydrogen fuel through artificial photosynthesis May 3rd, 2018

Research gives new ray of hope for solar fuel April 27th, 2018

Printing/Lithography/Inkjet/Inks/Bio-printing

Making carbon nanotubes as usable as common plastics: Researchers discover that cresols disperse carbon nanotubes at unprecedentedly high concentrations May 15th, 2018

New 4-D printer could reshape the world we live in March 20th, 2018

Leti & Mapper announce cyber-security breakthrough that encrypts individual chips with a code: Low-Cost Cyber-Security Breakthrough that Encrypts Individual Chips With a Unique Code Presented at SPIE Advanced Lithography 2018 in San Jose March 2nd, 2018

Basque researchers turn light upside down February 23rd, 2018

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project