Developing Scanning Nano-Raman Spectroscopy
Abstract
Scanning probe microscopes (SPM) are used to obtain topographical information with nanometer spatial resolution. Acquiring simultaneous chemical information with Raman or Infrared spectroscopy would be a momentous step forward for nanotechnology. Such an instrument will find wide application in characterizing nanostructured materials and nanoscale integrated devices. The main obstacles in constructing such an instrument are (i) the inherent weakness of the Raman signal and (ii) the diffraction limit for lateral resolution ( ∼ 500 nm). Near-field Raman enhancements based on Surface Enhanced Raman Scattering can be achieved using metallized SPM probes. We are developing an apertureless near-field Raman spectrometer in which the signal is enhanced in the neighborhood of a metal coated AFM tip brought into the laser beam footprint on the sample. Preliminary measurements done on Methylene Blue dye using silver coated tips under green (514.5 nm) light demonstrate significant Raman signal enhancement. Prospects for further development of scanning nano-Raman spectroscopy will be discussed.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MAR.R1174M