Large-area topography analysis and near-field Raman spectroscopy using bent fibre probes

J Microsc. 2003 Jun;210(Pt 3):269-73. doi: 10.1046/j.1365-2818.2003.01142.x.

Abstract

We present a method for combined far-field Raman imaging, topography analysis and near-field spectroscopy. Surface-enhanced Raman spectra of Rhodamine 6G (R6G) deposited on silver nanoparticles were recorded using a bent fibre aperture-type near-field scanning optical microscope (NSOM) operated in illumination mode. Special measures were taken to enable optical normal-force detection for control of the tip-sample distance. Comparisons between far-field Raman images of R6G-covered Ag particle aggregates with topographic images recorded using atomic force microscopy (AFM) indicate saturation effects due to resonance excitation.