Design and evaluation of micro-cutting tools for local planarization

Following the skyrocketing demands for micro applications, various micro-cutting tools have been investigated up to a diameter of a few μm; however, most of them are limited in terms of tool geometry due to the fabrication techniques used. In this study, we present 30-μm-diameter micro-mechanical cutting tools with 3D cutting edges fabricated using FIB systems. Their geometries were inspired by macroscale cutting tools. Tools were fabricated with one, two, four, and multiple-lattice cutting edges, and their performances were compared with a bulk cylinder tool with no pattern. A local planarization system was constructed for the nanoporous structure. To assess performances, the height and roughness of the structures were measured after the planarization. The structure height was controlled at 1 μm, and a surface roughness of 20 nm was achieved. Among the patterns, the best surface roughness was obtained with the multiple-lattice cutting edges, and surface roughness improved as the number of edges increased. The tool showed little wear at the edges after several rounds of planarization. These results will contribute to the development of an intermediate process for nanoscale 3D printing, and also to direct microscale cutting of a structure.