Three-dimensional measurement system with microtactile sensor

Abstract

With the development of micro-technology new measurement methods for microsystem components are increasingly required. Many Institutes have developed new methods for these requirements recently. In the Physikalisch-Technische Bundesanstalt (PTB) a precise three dimensional measurement system is currently under development. The probing process of a 3d tactile sensor which has been developed in cooperation with the Institute for Microtechnology of the Technical University of Braunschweig, will be investigated using this precise 3d measurement system. The 3d precision measuring machine consists of a coarse and a fine stage. The coarse stage has a travel range of 25 mm ×25 mm ×13 mm with a resolution of 50 nm. The fine stage mounted on top of the coarse stage and driven by piezoelectric transducers in three axes has a travel of 80 μm and is controlled by integrated capacitive gauges with a resolution of 1.22 nm. A metrology frame has been added on the fine stage, consisting of a three axis laser interferometer for simultaneous measurement of the displacement in all axes. The specimens to be measured are set in the measurement frame and the probing ball of the tactile sensor is centered at the cross point of the three laser beams (Abbe measurement principle). The measurement system is aimed at a 3d uncertainly < 100 nm for the investigation of tactile sensors in a measuring range of 25 mm ×25 mm ×13 mm.