A 2D nano-positioning system with sub-nanometric repeatability over the millimetre displacement range

We propose a 2D displacement control system with sub-nanometric repeatability on position over the millimetre travel range on both axes. It could be useful for nanofabrication processes or other applications related to the nanotechnology community. In our case, the apparatus is planned to be used in atomic force microscopes and lithography systems as a sample-holding device. The method is based on a heterodyne interferometric sensor and a home-made high frequency phase-shifting electronic board. This paper presents the complete mechanical system and gives experimental results showing a repeatability of 0.5 nm over a moving range of 5 mm.