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The Atomic Force Microscope (AFM) is emerging as an excellent platform for developing Near-field Scanning Optical Microscopes (NSOM) and Tip-enhanced Raman Spectroscopy. Unlike the conventional "shear-force" feed-back system carried out by the means of tuning forks, the XE-NSOM uses the XE-series' state-of-the-art closed loop feedback system only available through the prowess of XE-AFMs' high performing Z-scanner. In the past, NSOM research has been limited to relying on the shear-force feedback systems in order to maintain proper working distance. With the XE-NSOM, researchers are now able to carry out aperture/apertureless cantilever-based NSOM experiments with the highest feedback performance of XE series AFM. We have combined the Near-field Optical technique to the laboratorial XE-AFM designed and tailored specifically for non-contact research applications. The XE-NSOM provides independent axes for both the NSOM and the AFM laser paths, allowing the laser spots to be independently focused and controlled. Additionally, the XE-NSOM adopts a high performance Z scanner with a flexure guided scan system which is completely decoupled from the XY scanner. As a result, the XE-NSOM can simultaneously acquire nanometer resolution AFM data as well as cantilever based NSOM images. This now enables a direct seamless comparison of AFM experimental data and near-field optical data. In particular, the non-contact topographical information of the sample together with the NSOM information will provide researchers with valuable insight of the materials. We couple this same AFM head to a high performance Raman spectrometer to achieve the reflection mode of the tip-enhanced Raman spectroscopy. The capability of obtaining Raman spectroscopy and surface topography information simultaneously with nanoscale spatial resolution is of great importance for both basic research and technology applications. Tip-enhanced Raman spectroscopy in reflection mode specially can measure the nanoscale characterization of non-transparent samples, such as silicon, which cannot be measured in transmission mode. This development gives us big enhancement in industrial applications. |