Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

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

Clues to inner atomic life from subtle light-emission shifts: Hyperfine structure of light absorption by short-lived cadmium atom isotopes reveals characteristics of the nucleus that matter for high precision detection methods July 3rd, 2015

Pioneering Southampton scientist awarded prestigious physics medal July 3rd, 2015

Groundbreaking research to help control liquids at micro and nano scales July 3rd, 2015

Discovery of nanotubes offers new clues about cell-to-cell communication July 2nd, 2015

Nanospiked bacteria are the brightest hard X-ray emitters July 2nd, 2015

Chemistry

Groundbreaking research to help control liquids at micro and nano scales July 3rd, 2015

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Discoveries

Clues to inner atomic life from subtle light-emission shifts: Hyperfine structure of light absorption by short-lived cadmium atom isotopes reveals characteristics of the nucleus that matter for high precision detection methods July 3rd, 2015

Groundbreaking research to help control liquids at micro and nano scales July 3rd, 2015

Producing spin-entangled electrons July 2nd, 2015

NIST Group Maps Distribution of Carbon Nanotubes in Composite Materials July 2nd, 2015

Announcements

Clues to inner atomic life from subtle light-emission shifts: Hyperfine structure of light absorption by short-lived cadmium atom isotopes reveals characteristics of the nucleus that matter for high precision detection methods July 3rd, 2015

Pioneering Southampton scientist awarded prestigious physics medal July 3rd, 2015

Groundbreaking research to help control liquids at micro and nano scales July 3rd, 2015

NIST Group Maps Distribution of Carbon Nanotubes in Composite Materials July 2nd, 2015

Energy

New technology using silver may hold key to electronics advances July 2nd, 2015

Visible Light-Sensitive Photocatalysts Used for Purification of Contaminated Water in Iran June 30th, 2015

June 29th, 2015

Making new materials with micro-explosions: ANU media release: Scientists have made exotic new materials by creating laser-induced micro-explosions in silicon, the common computer chip material June 29th, 2015

Solar/Photovoltaic

Making new materials with micro-explosions: ANU media release: Scientists have made exotic new materials by creating laser-induced micro-explosions in silicon, the common computer chip material June 29th, 2015

Spain nanotechnology featured at NANO KOREA 2015 June 26th, 2015

Stanford researchers stretch a thin crystal to get better solar cells June 25th, 2015

Toward tiny, solar-powered sensors: New ultralow-power circuit improves efficiency of energy harvesting to more than 80 percent June 23rd, 2015

Printing/Lithography/Inkjet/Inks

New technology using silver may hold key to electronics advances July 2nd, 2015

New conductive ink for electronic apparel June 25th, 2015

Leti to Present Solutions to New Applications Using 3D Technologies at SEMICON West LetiDay Event, July 14: Leti Experts also Will Speak at TechXPOT Session on MEMS and STS Session on Lithography Cost-and-Productivity Issues Below 14nm June 22nd, 2015

$8.5M Grant For Developing Nano Printing Technology: 4-D printing to advance chemistry, materials sciences and defense capabilities June 18th, 2015

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project