title: Topographical and chemical microanalysis of surfaces with a scanning probe microscope and laser-induced breakdown spectroscopy
abstract: Spatially resolved chemical imaging is achieved by combining a fiber-optic scanning probe microscope with laser-induced breakdown spectroscopy in a single instrument, TOPOLIBS. Elemental composition of surfaces can be mapped and correlated with topographical data. The experiment is conducted in air with minimal sample preparation. In a typical experiment, surface topography is analyzed by scanning a sharp fiber-optic probe across the sample using shear force feedback. The probe is then positioned over a feature of interest and pulsed radiation is delivered to the surface using a nitrogen laser. The pulse vaporizes material from the surface and generates a localized plasma plume. Optical emission from the plume is analyzed with a compact UV/visible spectrometer. Ablation crater size is controlled by the amount of laser power coupled into the probe. Sampling areas with submicrometer dimensions are achieved by using reduced laser power.
authors.affiliation: Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena 91125, USA.
authors.initials: D
authors.lastname: Kossakovski
authors.initials: JL
authors.lastname: Beauchamp