Laboratory of Physics of Interfaces and Thin Films

- The instrument developed in collaboration with Horiba Jobin-Yvon, uses the TERS effect. (Tip Enhanced Raman Spectroscopy). In this combination between a scanning probe microscope (SPM) and a Raman spectrometer, a noble metal tip is used to generate a strong amplification of the local electromagnetic field. Optical interaction between the enhanced field and the sample results in enhanced Raman scattering.

- Using simultaneously near-field imaging (STM or AFM) and spectral acquisition point by point, multi walled carbon nanotubes Raman images of about 30 nm lateral resolution can be obtained. The high optical resolution offered by the SPM is thus combined with chemical information of Raman spectroscopy.

- Our research activities focus also on the characterization of self-assembled monolayers of organic molecules such as azobenzene and pentacene, graphene, silicon and diamond nanoparticules.

- In order to study the polarization properties of the Raman signal using our instrumentation, we have developed a phenomenological model of Raman tensor describing the interaction between the tip and the incident and diffused field. This tensor fully characterizes the sample polarimetric properties. In addition, we have developed a methodology to determine the stress magnitude in silicon semiconductors.

- This method successfully applied to cubic crystal structures of well-known orientation, could also be extended to other symmetries; this way the stress tensor in a Si/SiGe system used in microelectronics industry, could be experimentally deduced.

Contact : Razvigor Ossikovski