Atomic-scale positioning reference grid system for miniature robots with embedded scanning tunnelling capability

The concept of a nanorobotic platform based on a fleet of miniature instrumented robots capable of atomic-scale operations has been proposed. Although such an approach offers significant advantages compared to more traditional approaches, many technical challenges remain to be resolved. As such, being able to position the instrument embedded onto each robot with atomic-scale precision is a critical, yet challenging problem. All known positioning techniques, including, but not limited to, interferometry, cannot be applied in this case. This paper suggests a novel approach where coarse positioning through optical means is coupled to surface analysis to achieve atomic scale precision. A special line-based pattern engraved on a surface is used to guide and accelerate the robot´s instrument positioning by delimiting a matrix of work windows where atomic positioning through atom counting takes places. The NanoWalker research project serves as an implementation contest for this grid. Its current version is etched on Highly Oriented Pyrolytic Graphite (HOPG) and imaged with commercial Scanning Probe Microscopes (SPM).