Near-field Raman spectroscopy

✍ Scribed by Jerôme Grausem; Bernard Humbert; Michel Spajer; Daniel Courjon; André Burneau; Joel Oswalt

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 435 KB
• Volume: 30
• Category: Article
• ISSN: 0377-0486
• DOI: 10.1002/(sici)1097-4555(199909)30:9<833::aid-jrs455>3.0.co;2-#

✦ Synopsis

An optical device was constructed to collect near-field Raman spectra (NFRS) and far-field scattering Raman spectra simultaneously on the same sample area. In Raman applications where the studied samples do not enjoy any advantages of resonance effects, the nanoprobe may be used only as a nanodetector in order to avoid damage of the tip by the necessary laser powers. The silicon-based samples, which are either calibrated grid or a single crystal, were studied by NFRS and conventional scattering Raman spectroscopy. The nearfield Raman signal of silicon is divided by at least four when the tip-silicon substrate distance is separated by a 100 nm layer of oxide. Moreover, between the NFR spectrum and the far-field spectrum, on the single crystal, a shift of about 10 cm -1 is displayed. Some interpretations are discussed. These experiments confirm the potential of the NFRS already emphasized previously in the literature.