Voice coil-based scanning probe microscopy

We present a novel system for large-area scanning probe microscopy (SPM) measurements based on minimum counter-force linear guidance mechanisms, voice coils, interferometers and fuzzy logic-based feedback loop electronics. It is shown that voice coil-based actuation combined with interferometry can be a good alternative to piezoceramic positioning systems, providing fast and still sufficient, precise displacements which range from nanometers to millimeters. Using fuzzy logic feedback control, it can be actuated even with only a few low-cost components, like a cheap single-chip microcontroller. As the final positioning resolution can be made independent on the electronics output resolution, the system can reach high positioning resolution even on very large scan sizes. This is a key prerequisite for developing novel generations of SPMs that would combine, in a very large range, with high-speed imaging.