ON THE SPATIAL-RESOLUTION OF UNCOATED OPTICAL-FIBER PROBES IN INTERNAL-REFLECTION NEAR-FIELD SCANNING OPTICAL MICROSCOPY

We present conclusive experimental quantitative evidence of the resolu tion limit of uncoated optical fiber probes in the internal reflection mode. Additionally, we present a new technique for unambiguously dete rmining the resolution of a near-field scanning optical microscope wit hout topographical influences. A sample with nearly no topography but with a large dielectric step junction was created by evaporating a thi n chromium layer on a silicon wafer and subsequently cleaving the wafe r. The cleaved edge is then scanned over the step junction, allowing a quantitative determination of the lateral resolution without topograp hical influences. (C) 1998 Elsevier Science B.V. All rights reserved.