ON THE LIMITS OF THE SPECTROSCOPIC ABILITY OF AFM AND THE INTERACTION BETWEEN AN AFM TIP AND A SAMPLE

The spectroscopic ability of the atomic force microscopy (AFM) is considered and limits are found on the parameters of a small object which may be detected by means of AFM. For example, in the attractive mode it is shown that AFM is able to distinguish between small objects consisting of different materials provided their volumes are greater than (5 X 5 X 5) atoms. Moreover, the interaction between an AFM tip and a plane sample is examined in the framework of the continuous approach. The choice of a paraboloid AFM tip is substantiated.