ON THE RECOVERY OF THE SPECTROSCOPIC IMAGE IN ATOMIC-FORCE MICROSCOPY

The principle possibility of the detection of the sort of material a s urface consists of (in other words, obtaining the spectroscopic, or '' Hamaker constant'' image of the surface) is proven for the atomic forc e microscopy method. It is shown that the problem can be reduced to th e Fredgolm integral equation of the first kind with a core of the Hilb ert-Schmidt type. This problem is demonstrated to have a unique soluti on, provided the model case of exact measurements and the surface topo graphy is known in advance. It is shown that the latter can be conside red as the topography obtained in the contact mode. The possibility of the spectroscopic image recovery for the measurements with errors is discussed. As an example, obtaining the Hamaker constant is demonstrat ed for an example of the surface consisting of two different materials . (C) 1996 American Vacuum Society.