Raman spectroscopy of adsorbates on semiconductors by means of SERS effect

Autor: F.R. Ladan, L.G. Quagliano, B. Jusserand
Rok vydání: 1995
Předmět:
Zdroj: Physica Status Solidi (a). 152:219-225
ISSN: 1521-396X
0031-8965
DOI: 10.1002/pssa.2211520122
Popis: An application of surface enhanced Raman scattering (SERS) to the surface characterization of semiconductors is reported by evaporating an Ag island film onto the surface of the materials. The surface sensitivity of the Raman effect at the metal surface is used for the study of molecules absorbed onto the semiconductors. With this method there is enhanced Raman scattering from the surface because the discontinuous Ag layer produces large electromagnetic enhancement at each Ag particle. SERS spectra are observed from tris(bipyridine)ruthenium, Ru(bpy) 3 2+ , molecules adsorbed on Si, GaAs, InP, silver, and glass substrates onto which an Ag island film has been evaporated. The spectral differences observed between the spectra from the molecules adsorbed on the semiconductors and on the glass and silver substrates allow us to affirm that the SERS signals arise from the substrate surface and not from the Ag island film. Raman scattering cannot be detected from surfaces without the deposited Ag film because the vibrational spectra of molecules adsorbed on the surface are too weak to be detected. These results prove that by using the Ag overlayer method is should be possible to study the properties of adsorbed species on semiconductor surfaces. This suggests the possibility of utilizing the SERS effect as a new surface probe of the semiconductor surface considering that Raman spectroscopy can give detailed information about the state of chemical species on the surface.
Databáze: OpenAIRE
Externí odkaz: