IMPACT OF ATOMIC RELAXATION ON THE BREAKS OF CONSTANT FORCE SURFACES IN AFM

A calculation model for determination of the shapes of the constant fo rce surfaces and profiles of lateral forces for the case of the AFM ti p scanning the closely packed lattice in contact mode is proposed. Ato mic relaxation is taken into account in this model. The existence of b reaks on constant force surfaces, which was predicted earlier in an ap proximation of the fixed lattice, is confirmed. It is shown that due t o non-zero atomic mobility, breaks appear for smaller scanning forces than assumed earlier. The shapes of the continuous constant force surf aces and profiles of lateral force components are computed. These resu lts may be used for diagnostics of point defects on the surface. (C) 1 998 Elsevier Science B.V. All rights reserved.