Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Broadband coherent anti-strokes Raman spectroscopy characterization of polymer thin films

Published

Author(s)

Lee J. Richter, M C. Gurau, Zachary Schultz

Abstract

Broadband coherent anti-Stokes Raman spectroscopy (CARS) is demonstrated as an effective probe of the polymer thin film materials. A simple modification to a commercially available 1 kHz SFG spectrometer permits acquisition of CARS spectra for polymer thin films with an aspect ratio relevant to device applications. CARS spectra are compared to the conventional Raman spectra of polystyrene and the resonance enhanced Raman spectra of poly(3-hexylthiophene). The CARS spectra obtained consistently demonstrate a 1-2 orders of magnitude signal enhancement compared to spontaneous Raman scattering. The sensitivity of the CARS measurement is limited by the damage threshold of the samples. The Fresnel coefficients associated semiconducting (Si), conducting (Au), and insulating (Quartz) substrates has a dramatic effect on the detected signal intensity. The strongest signals are obtained from Quartz surfaces. Similar to surface enhanced Raman scattering (SERS), Au also gives a large signal, but contrary to SERS no surface roughening is necessary. The CARS measurements present here demonstrate methodology for the rapid acquisition of high sensitivity spectra for polymer thin film samples.
Citation
Applied Spectroscopy
Volume
60
Issue
10

Keywords

"nonlinear spectroscopy", "Raman", "thin films", "broadband CARS"

Citation

Richter, L. , Gurau, M. and Schultz, Z. (2006), Broadband coherent anti-strokes Raman spectroscopy characterization of polymer thin films, Applied Spectroscopy (Accessed June 14, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created August 2, 2006, Updated February 19, 2017