title: Enhancing Raman signals with an interferometrically controlled AFM tip.
abstract: We demonstrate the upgrade of a commercial confocal Raman microscope into a tip-enhanced Raman microscope/spectroscopy system (TERS) by integrating an interferometrically controlled atomic force microscope into the base of an existing upright microscope to provide near-field detection and thus signal enhancement. The feasibility of the system is demonstrated by measuring the Raman near-field enhancement on thin PEDOT:PSS films and on carbon nanotubes within a device geometry. An enhancement factor of 2-3 and of 5-6 is observed, respectively. Moreover, on a nanotube device we show local conductivity measurement and its correlation to Raman and topography recordings. Upgrading an existing upright confocal Raman microscope in the demonstrated way is significantly cheaper than purchasing a complete commercial TERS system.
authors.affiliation: Institute of Nanotechnology, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany.
authors.forename: Matti
authors.initials: M
authors.lastname: Oron-Carl
authors.forename: Ralph
authors.initials: R
authors.lastname: Krupke
mesh_terms: D004867:Equipment Design; D018625:Microscopy, Atomic Force / Q000295:instrumentation*; D018613:Microscopy, Confocal / Q000295:instrumentation*; D037742:Nanotubes, Carbon / Q000648:ultrastructure; D011137:Polystyrenes / Q000032:analysis; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*; D013876:Thiophenes / Q000032:analysis
chemical_list: D037742:Nanotubes, Carbon; D011137:Polystyrenes; D013876:Thiophenes; C533756:poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)