Design and calibration of a parallel-moving displacement generator for nano-metrology

A displacement generator is realized which enables the calibration of a wide variety of displacement-measuring probes, such as probes of roundness testers, roughness testers and stand-alone type scanning probe microscopes (SPMs), in the range of 12 mu m with a standard uncertainty below 1 nm. A digital piezo translator (DPT) drives a flat mirror which serves as the calibration platform. This mirror is locked to an elastic, hysteresis-free, monolithic parallel guide. Calibration of the platform displacement is carried out by various methods including tunable and stabilized lasers, Fabry-Perot interferometry and laser interferometry. The system is calibrated with a standard uncertainty of about 0.1 nm using three independent methods. As an example the calibration of an SPM using 0.5 mu m generated steps is shown.