attoPUBLICATIONS attoCATALOG-2017/18 | Page 96

Retrieve nano-features over millimeter ranges! closed loop scanning & global sample coordinates Science and technology delve deeper and deeper into the nanoworld. In particular, scanning probe & confocal microscopy have been concerned with features on the nanoscale ever since its invention. Reliably scanning over tens of micrometers range down to a few hundred nm is comparatively easily achieved by using piezo based scanners. However, using piezo-based scanners usually relies on the assumption that the relation between applied voltage and displacement is linear. In reality, most scanners show large non-linear behaviour and hysteresis, especially for large scan ranges. Creep, i.e. drift in position after approaching a certain location, is a further phenomenon which is common to all piezo scanners. In many experiments, reproducibly locating a small feature on a surface is crucial, and sometimes hysteresis and non-linearity in the acquired image are not acceptable. Sometimes, SPM images need to be evaluated for particularly and for the specific mutual distances of certain features, and hence, any distortions due to those nonlinearities may impede such analyses significantly. total available range up to5 mm Much more often, however, finding a certain region of interest