IMAGING OF ORGANIC MOLECULAR FILMS USING A SCANNING NEAR-FIELD OPTICAL MICROSCOPE COMBINED WITH AN ATOMIC-FORCE MICROSCOPE

A scanning near-held optical microscope combined with an atomic force microscope is described. The instrument uses a microfabricated force-s ensing cantilever made of single-crystal silicon with an integrated p- n diode at its end as a microphotodetector. The photosensitive cantile ver efficiently detects the light scattered by the tip in the evanesce nt field generated by illuminating the sample by total internal reflec tion. Simultaneously the surface force is detected by monitoring the d eflection of the cantilever. Both scanning near-field optical microsco pe and atomic force microscope images of a compact disk grating and a photosynthetic protein membrane were obtained, The membrane was deposi ted on the glass substrate using the Langmuir-Blodgett technique. The features in the scanning near-field optical microscope images are simi lar to those in the atomic force microscope, The possible crosstalk be tween the optical and the topography signal is discussed. (C) 1996 Ame rican Vacuum Society.