A preliminary study of spatial resolution enhancement of confocal and triangulation displacement meters using contact...

This paper presents a method for the spatial resolution enhancement of confocal and triangulation meters using cantilever probes. Integration of a cantilever with existing commercially available meters is substantially eased by the absence of feedback control of the cantilever position. Confocal and triangulation meters are used for a number of applications in research and industrial settings including thickness measurements, topography measurements, step height measurements, flatness measurements, and profile measurements. These instruments provide a vertical (out-of-plane) resolution of a few nanometers. However, they are limited in their spatial resolution to the laser beam diameter, which is typically larger than 2 microm and often about 20 microm. Using a cantilever probe to make contact with the sample, the lateral resolution of standard commercial instruments can be improved to less than 1 microm.