A simulation study of multi-atom tips and estimation of resolution in atomic force microscopy

The structure of the atomic arrangement at the apex of the tip plays an important role in the atomic force microscope (AFM) images. Computer topographs of the sample surface were simulated with various tip structures at the apex. We have described a scheme to estimate the lower limit of the lateral resolution of AFM with a mono-atomic tip. It is observed that in the contact mode of operation, resolution and sensitivity of AFM is comparable to that of STM.