Abstract: A high degree of measurement reproducibility is assured for the life of the tip of a probe-based instrument such as an atomic force microscope (AFM) by periodically operating the instrument in a tip cleaning mode to remove contaminants from the tip. The instrument is operated to interrupt the scanning operation and cause the probe to interact with the cleaning medium so as to remove contaminants from at least the pointed end portion of the tip. Tip cleaning may be achieved, for example, by ramming the tip vertically into the sample itself or into another cleaning medium located adjacent the sample. Alternatively, the tip can be moved laterally over the sample, a sticky material, a brush-like material, a ribbed material, or another material having surface characteristics that remove contaminants from the tip.

Abstract: The mechanical properties of a surface are measured by using a pointed tip on the end of a bendable cantilever such that with force on the other end of the cantilever the tip can be pushed into the surface using the bending of the cantilever as the measure of the constant force. The indentation, scratch, or wear created by the application of forces between the tip and sample is then measured with the same tip and cantilever by raising the cantilever off the surface and putting it into oscillation. The tip is then scanned over the area where the indentation was made with the tip tapping on the surface in order to image the surface.