Direct observation of the tip shape in scanning probe microscopy

Abstract

In this study we report on the first direct observation of the real shape of the atomic force microscopy (AFM) tip using the AFM technique itself, utilizing a specially designed sample geometry. This is the first report of the so-called inverse AFM mode in which the tip is actually used as the sample and vice versa. We propose how this method can, with a very high accuracy, be used for studying objects, e.g., biomolecules, that are attached to the usual AFM cantilever tip. Finally, we discuss how this method can significantly increase the reliability of the obtained AFM images.