Evaluation of AFM tips using nanometer-sized structures induced by ion sputtering

In this study, we report on a process for the fabrication of nanometer-sized surface structures using low-energy Ar+ sputtering of InP surfaces. The dimension of these structures (≤100 nm) and the distance between them can be tuned by the parameters of the sputter process (sputter time, ion energy, ion incidence angle, sputter time, and ion current density or ion flux, respectively). With the help of surfaces prepared by this way, we have evaluated the influence of the actual AFM tip quality on the measured surface topography. Furthermore, we have shown that the tip quality has a strong influence on the surface roughness parameters extracted from the AFM images particularly for surfaces with a low surface roughness (∼1 nm) as generally obtained by means of thin film technologies.