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

Research Study: MetaSOLTM Shatters Solar Panel Efficiency Forecasts with Innovative New Coating: Coating Provides 1.2 Percent Absolute Enhancement to Triple Junction Solar Cells December 2nd, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Quantum obstacle course changes material from superconductor to insulator December 1st, 2016

Throwing new light on printed organic solar cells December 1st, 2016

Imaging

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Controlled electron pulses November 30th, 2016

Laboratories

Working under pressure: Diamond micro-anvils with huge pressures will create new materials October 19th, 2016

Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge October 15th, 2016

Scientists Find Static "Stripes" of Electrical Charge in Copper-Oxide Superconductor: Fixed arrangement of charges coexists with material's ability to conduct electricity without resistance October 14th, 2016

Tomoyasu Mani Wins 2016 Blavatnik Regional Award for Young Scientists: Award recognizes his work at Brookhaven Lab to understand the physical processes occurring in organic materials used to harness solar energy October 13th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Research Study: MetaSOLTM Shatters Solar Panel Efficiency Forecasts with Innovative New Coating: Coating Provides 1.2 Percent Absolute Enhancement to Triple Junction Solar Cells December 2nd, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Quantum obstacle course changes material from superconductor to insulator December 1st, 2016

Throwing new light on printed organic solar cells December 1st, 2016

Nanomedicine

Nanobiotix Provides Update on Global Development of Lead Product NBTXR3: Seven clinical trials across the world: More than 2/3 of STS patients recruited in the “act.in.sarc” Phase II/III trial: Phase I/II prostate cancer trial now recruiting in the U.S. November 28th, 2016

From champagne bubbles, dance parties and disease to new nanomaterials: Understanding nucleation of protein filaments might help with Alzheimer's Disease and type 2 Diabetes November 24th, 2016

Nanopolymer-modified protein array can pinpoint hard-to-find cancer biomarker November 17th, 2016

Nanotechnology Treatment Found to Inhibit Mesothelioma Tumor Growth November 16th, 2016

Discoveries

Research Study: MetaSOLTM Shatters Solar Panel Efficiency Forecasts with Innovative New Coating: Coating Provides 1.2 Percent Absolute Enhancement to Triple Junction Solar Cells December 2nd, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Quantum obstacle course changes material from superconductor to insulator December 1st, 2016

Throwing new light on printed organic solar cells December 1st, 2016

Announcements

Research Study: MetaSOLTM Shatters Solar Panel Efficiency Forecasts with Innovative New Coating: Coating Provides 1.2 Percent Absolute Enhancement to Triple Junction Solar Cells December 2nd, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Quantum obstacle course changes material from superconductor to insulator December 1st, 2016

Throwing new light on printed organic solar cells December 1st, 2016

Research partnerships

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Quantum obstacle course changes material from superconductor to insulator December 1st, 2016

Novel silicon etching technique crafts 3-D gradient refractive index micro-optics November 28th, 2016

Single photon converter -- a key component of quantum internet November 28th, 2016

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