Near-Field Tip Enhanced Raman Analysis of Carbon Nanomaterials

• Main Authors: Chang-Bo-Hao, 張博皓
• Other Authors: Su-Hua Chen
• Format: Others
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/94964249907996000825

碩士 === 國立東華大學 === 材料科學與工程學系 === 104 === This thesis focuses on the preparation and measurement of carbon nanotube and graphene in nanoscale using tip-enhanced Raman scattering (TERS). The goal is to study the Raman spectral shift caused by local defects and structural variations with nanoscale spatial resolution. To enhance the TERS signal effectively, we prepare Au and Ag tips with clean and smooth surfaces (pollution forbidden) as well as sharp ends (Radius of curvature <100 nm) for 640 nm and 532 nm laser, respectively. At the same time, Au substrates with atomically-flat terraces also well prepared by Au evaporation at high temperature in order to prevent from hiding the surface morphology of our samples. TERS provides simultaneously not only the local Raman spectrum with high sensitivity but also the sample topography with nanometric lateral resolution. Therefore, TERS is one of the ultra-high spatial resolution and local chemical information methods. Far-field Raman spectroscopy is used to preliminarily check whether we succeed to transfer only one graphene layer on an au substrate. On the other hand, near field TERS signal provides simultaneously Raman spectrum and topographical comparison. Finally, our resolution of near-field Raman spectroscopy reached 6~8 nm.