Development of a 3D Tunneling Current Probing System for Micro- and Nano-Coordinate Metrology

The demands for precision measurement of three dimensional micro-and nanogeometries over a large area have rapidly increased during the last few years. To meet such requirements, many different nanometre resolving 3D capable probing sensors and corresponding 3D positioning systems to operate the sensors for 3D measurements have been developed. The mechanical contact-free, electrical work piece probing based on the scanning tunneling microscopy principle offers new possibilities for 3D micro coordinate measurements as well as for nanometre resolved topography measurements in micro-and nanometrology. This paper introduces an updated version of this probing sensor system extended with a 3D movable piezo scanner to directly detect its probing direction. With the magnitude and the direction of the contact vector forwarded to the position control of the nanopositioning and nanomeasuring machine NMM-1 all of the 3D measurement commands of NMM-1 can be utilized, allowing 3D surface scans and especially 3D free-form surface scans.