Guide to Best Practices for AFM Users

The aim of this chapter is a practical guide to help the atomic force microscopy (AFM) user effectively implement some of the methodologies and understand the various artifacts and associated challenges encountered in practical imaging. First, the chapter deals with issues of vertical (quasi-static) force measurements versus Z displacement, derived from (a) the significant angle of inclination of the cantilever relative to sample surface, (b) nonlinearity in the split-photodiode measurement of laser spot displacement, (c) geometric optics and interferometric effects related to the laser beam trajectory, and (d) thermal drift in the baseline (zero) of force. Next, the chapter focuses on complications that are instead due to physical interactions at the tip-sample interface. These physical interactions affect most types of AFM use including single-point force curve measurements or imaging methods such as topography and phase.