DEDUCING STRUCTURAL VARIATIONS OF THE APEX OF PROBES USED IN NEAR-FIELD OPTICAL MICROSCOPY THROUGH SIMULTANEOUS MEASUREMENT OF SHEAR FORCE AND EVANESCENT INTENSITY

We propose a simple method employing the simultaneous detection of eva nescent intensity and shear force to deduce variations in the near-fie ld optical morphology of the apex of the probes used in near-field mic roscopy. Fabrication of our probes involves sharpening by chemical etc hing, metal coating, and removal of metal from the apex. We show that through the simultaneous measurement of shear force and evanescent int ensity, it is possible to detect variations in the optical morphology of the very apex of the probes during near-field imaging by a scanning near-field optical microscope. (C) 1996 Optical Society of America