Force-distance curves by AFM

Since 1989, the atomic force microscope (AFM) has emerged as a useful tool in studying surface interactions by means of force-distance curves, and a great deal of work has been carried out on both its theoretical and experimental issues. AFM is able to acquire force-distance curves from every kind of surface, with high lateral (1 Å), vertical (0.1 Å) and force (1 pN) resolution. Moreover, the study of force-distance curves provides a deeper knowledge of the physics of contact, and hence of all the phenomena connected with AFM imaging techniques. In this article, we review force-distance curve theory, and show through curves acquired with a home-made microscope the main surface interactions that can be revealed.