Effect of cutting direction on nanomachining of copper when using a three-sided pyramidal AFM tip

In this paper, a three-sided pyramidal AFM tip was used to machine copper using both face forward and edge forward directions. Different process outcomes are expected due to such directional variations. However, this paper aims further to quantify such changes, including differences in groove depths, pile-up heights, and surface roughness, as well as with respect to groove formation mechanisms and relative stability of the process. To achieve this, the study also includes analyzing data recorded during nanomachining via the built-in position-sensitive photo-detector of AFM instruments. Such data correspond to lateral and torsional deflections of the cantilever on which the AFM tip is mounted. The experiments confirmed that significant changes in groove pile-ups, depths, and widths took place when these two cutting directions were analyzed. Additionally, cutting via chip formation was observed in the face forward direction, whereas only ploughing was seen in the edge forward direction. Conversely, no considerable difference between the surface roughness along each groove length for each of these directions was found. Finally, substantial contrast between the two directions was noticed when analyzing the data acquisition output. In particular, the induced vertical and torsional motions of the cantilever were generally more stable along the edge forward direction