SCANNING NEAR-FIELD OPTICAL MICROSCOPY SPECTROSCOPY OF THIN ORGANIC FILMS/

We have used a scanning near-field optical microscope to investigate t he optical properties of a thin organic film consisting of poly(phenyl ene vinylene) and tris(8-hydroxy)quinoline aluminum. Near-field optica l images taken in transmission mode using a 488 nm laser light reveale d numerous ''dark spots'' scattered randomly across the filmy however, the dark spots were not related to the surface topography. These dark spots ranged in size from 100-300 nm in diameter. The nature of the d ark spots was attributed to an increase in the absorption at 488 nm as a result of local variations in the poly(phenylene vinylene) film. (C ) 1996 American Vacuum Society.