Scanning capacitance microscopy

Abstract

A novel mechanically scanned and non-contacting surface profiling instrument has been developed in which a fine wire probe is raster scanned over the surface of the sample under examination. Measurement of the modulated capacitance between the probe and the vibrated sample is used to maintain the probe just above the surface. In the prototype instrument described, an in-plane resolution better than 2 mu m is achieved by the use of an etched tungsten wire probe, while the perpendicular resolution is 6 nm. Both insulating and conducting samples may be scanned and the technique makes it possible to measure electrical properties of the surface under the probe as well as the surface microtopography.