Characterizing AFM Tip Lateral Positioning Variability through Non-Vector Space Control-Based Nanometrology

Atomic force microscopy (AFM) based nanotechnology has been widely implemented in various fields for decades in light of its overwhelming advantages, such as nanometer spatial resolution, adaptability to liquid ambient, and various nanomechanical/electrical metrological approaches. It is noted that though AFM possesses imaging capability up to nanometer resolution, it is hard to achieve nanometer level positioning precision due to the existing system variability, especially the thermal drift, which distorts AFM images through relatively long capturing time. Since an AFM image is typically utilized as a global reference map to navigate its tip to the desired locations for precise measurement and manipulation, the system variability distorted image will definitely diversify the experimental results. Therefore, it is necessary to characterize the positioning variability for better experimental results evaluation and decision-making. Although various approaches were proposed to evaluate AFM positioning error, to our best knowledge, there is little research about characterizing its positioning variability precisely and systematically. In this study, we present a universal metrological approach to quantitatively measure AFM tip locating variability by developing a featureless spiral local scan strategy together with the non-vector space (NVS) navigation approach. As a demonstration, the proposed nanometrology was conducted on a specific AFM platform to unravel its positioning property.