Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Fluorescence Technique Measures Photoacid Distribution in Photoresists with Nanoscale Resolution

Schematic showing fluorescence from UV-activated fluorophores excited by 532 nm light that reveals nanoscale photoacid distribution (left).  Activated fluorophore concentration corresponds to the inverse of the original photoacid distribution (right).
Schematic showing fluorescence from UV-activated fluorophores excited by 532 nm light that reveals nanoscale photoacid distribution (left). Activated fluorophore concentration corresponds to the inverse of the original photoacid distribution (right).

Abstract:
A team of researchers from the NIST Center for Nanoscale Science and Technology, the University of Maryland, and Korea University (Seoul, Korea) has measured the nanoscale distribution of photoacid molecules in photoresists using a fluorescence technique originally developed to provide images of biological structures smaller than the wavelength of light.* Photoresists are light-sensitive chemicals used for manufacturing the semiconductor integrated circuits found in computers and other electronics. By measuring the chemical reactions in photoresists at a smaller length scale, this method potentially opens a path to manufacturing smaller electronic devices.

Fluorescence Technique Measures Photoacid Distribution in Photoresists with Nanoscale Resolution

Gaithersburg, MD | Posted on April 17th, 2013

In today's photoresists, chemical amplification of light allows for the use of low-brightness short-wavelength light sources, which enable smaller feature sizes to be printed at higher throughputs. Each individual photon activates a molecule which generates a photoacid. During post-exposure baking, the photoacid diffuses, rendering a volume of the resist soluble to developer. This improves the sensitivity, or photospeed, of the resist, but at the cost of degraded image resolution: a result of the photoacid diffusion. Until now, it has only been possible to infer indirectly where the photoacid molecules are produced or how they diffuse by analyzing the resist images after the resist is fully exposed, either before or after it is developed. A more direct measurement is critically needed, however, because the distribution of the photoacid molecules within a resist film limits the minimum feature sizes that can be produced on computer chips. Precise measurements can help photoresist manufacturers understand the processes that lead to loss of image contrast and develop measures to mitigate blur induced by photoacid diffusion.

To observe the location of the photoacid molecules more directly, the research team used a novel fluorescent dye that can be switched from a dark to bright state either by exposure to ultraviolet light or by reaction with a nearby acid molecule. Over time, they fit the fluorescent signal of each dye molecule to a two-dimensional distribution, allowing them to map the locations of the associated photoacid molecules with single-molecule sensitivity. The team also developed new statistical analysis methods that enable them to extract high-resolution information even when there is a very low concentration of fluorescent molecules. This method allows them to be confident that the behavior of the system is not changed by the presence of the fluorophores.

Ultimately, the researchers believe that these techniques will be useful for measuring nanoscale transport processes in a wide variety of soft-matter systems beyond photoresists, such as in polymers.

*Super-resolution optical measurement of nanoscale photoacid distribution in lithographic materials, A. J. Berro, A. J. Berglund, P. T. Carmichael, J. S. Kim, and J. A. Liddle, ACS Nano 6, 9496-9502 (2012).

####

About National Institute of Standards and Technology (NIST)
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

For more information, please click here

Contacts:
J. Alexander Liddle
301-975-6050

Copyright © National Institute of Standards and Technology (NIST)

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

NIST Publication Database:

Journal Web Site:

Related News Press

News and information

In borophene, boundaries are no barrier: Rice U., Northwestern researchers make and test atom-thick boron's unique domains July 17th, 2018

Tuning into quantum: Scientists unlock signal frequency control of precision atom qubits July 16th, 2018

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Nanometrics to Announce Second Quarter Financial Results on July 31, 2018 July 12th, 2018

Imaging

Oxford Instrumentsí 22 Tesla superconducting magnet system commissioned at the UAM, making it the most intense magnetic field available outside a large international facility July 12th, 2018

Alzheimer's breakthrough: Brain metals that may drive disease progression revealed: In brains affected by Alzheimer's, researchers identify chemically reduced iron species, with mineral forms including a magnetic iron oxide June 22nd, 2018

Laboratories

Carbon is the new black: Researchers use carbon nanotubes to develop clothing that can double as batteries July 10th, 2018

NIST Researchers Simulate Simple Logic for Nanofluidic Computing June 30th, 2018

Cleaning or Etching Items with Unique Geometries Requires Specialized Expertise June 27th, 2018

Govt.-Legislation/Regulation/Funding/Policy

In borophene, boundaries are no barrier: Rice U., Northwestern researchers make and test atom-thick boron's unique domains July 17th, 2018

Tuning into quantum: Scientists unlock signal frequency control of precision atom qubits July 16th, 2018

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

Carbon is the new black: Researchers use carbon nanotubes to develop clothing that can double as batteries July 10th, 2018

Nanomedicine

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Researchers identify cost-cutting option in treating nail fungus with nanotechnology: GW researcher Adam Friedman, M.D., studied the potential use of nitric oxide-releasing nanoparticles to improve onychomycosis treatment July 11th, 2018

New sensor technology enables super-sensitive live monitoring of human biomolecules July 3rd, 2018

Discoveries

In borophene, boundaries are no barrier: Rice U., Northwestern researchers make and test atom-thick boron's unique domains July 17th, 2018

Tuning into quantum: Scientists unlock signal frequency control of precision atom qubits July 16th, 2018

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Announcements

In borophene, boundaries are no barrier: Rice U., Northwestern researchers make and test atom-thick boron's unique domains July 17th, 2018

Tuning into quantum: Scientists unlock signal frequency control of precision atom qubits July 16th, 2018

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Research partnerships

In borophene, boundaries are no barrier: Rice U., Northwestern researchers make and test atom-thick boron's unique domains July 17th, 2018

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

Leti and Soitec Launch a New Substrate Innovation Center to Develop Engineered Substrate Solutions: Industry-inclusive hub promotes early collaboration and learning from substrate to system level July 11th, 2018

Leti & Partners Launch Pilot Program to Assess New Perception Sensors for Autonomous Vehicles July 5th, 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