Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

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

Laboratories

Nanoshuttle wear and tear: It's the mileage, not the age January 26th, 2015

Imaging

Visualizing interacting electrons in a molecule: Scientists at Aalto University and the University of Zurich have succeeded in directly imaging how electrons interact within a single molecule January 26th, 2015

News and information

Nanoparticles Increase Durability of Concrete Decorations in Cold Areas January 26th, 2015

Iranian Researchers Boost Solar Cells Efficiency Using Anti-Aggregates January 26th, 2015

Detection of Heavy Metals in Samples with Naked Eye January 26th, 2015

Engineering self-assembling amyloid fibers January 26th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Nanoshuttle wear and tear: It's the mileage, not the age January 26th, 2015

Visualizing interacting electrons in a molecule: Scientists at Aalto University and the University of Zurich have succeeded in directly imaging how electrons interact within a single molecule January 26th, 2015

The latest fashion: Graphene edges can be tailor-made: Rice University theory shows it should be possible to tune material's properties January 24th, 2015

Scientists 'bend' elastic waves with new metamaterials that could have commercial applications: Materials could benefit imaging and military enhancements such as elastic cloaking January 23rd, 2015

Nanomedicine

Engineering self-assembling amyloid fibers January 26th, 2015

Promising use of nanodiamonds in delivering cancer drug to kill cancer stem cells: NUS study shows that delivery of Epirubicin by nanodiamonds resulted in a normally lethal dosage of Epirubicin becoming a safe and effective dosage for treatment of liver cancer January 26th, 2015

Teijin to Participate in Nano Tech 2015 January 22nd, 2015

2nd International Conference on Infectious Diseases & Nanomedicine (December 15-18, 2015, Kathmandu, NEPAL) January 22nd, 2015

Discoveries

Visualizing interacting electrons in a molecule: Scientists at Aalto University and the University of Zurich have succeeded in directly imaging how electrons interact within a single molecule January 26th, 2015

Electronic circuits with reconfigurable pathways closer to reality January 26th, 2015

Nanoparticles Increase Durability of Concrete Decorations in Cold Areas January 26th, 2015

Iranian Researchers Boost Solar Cells Efficiency Using Anti-Aggregates January 26th, 2015

Announcements

Nanoparticles Increase Durability of Concrete Decorations in Cold Areas January 26th, 2015

Iranian Researchers Boost Solar Cells Efficiency Using Anti-Aggregates January 26th, 2015

Detection of Heavy Metals in Samples with Naked Eye January 26th, 2015

Engineering self-assembling amyloid fibers January 26th, 2015

Research partnerships

Visualizing interacting electrons in a molecule: Scientists at Aalto University and the University of Zurich have succeeded in directly imaging how electrons interact within a single molecule January 26th, 2015

Promising use of nanodiamonds in delivering cancer drug to kill cancer stem cells: NUS study shows that delivery of Epirubicin by nanodiamonds resulted in a normally lethal dosage of Epirubicin becoming a safe and effective dosage for treatment of liver cancer January 26th, 2015

Wearable sensor clears path to long-term EKG, EMG monitoring January 20th, 2015

Graphene enables all-electrical control of energy flow from light emitters: First signatures of graphene plasmons at telecommunications wavelength revealed January 20th, 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







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE