Application of sensor tilting for enhanced measurement of microstructures

Abstract

In the field of tactile surface probing, the contact point between the probing tip and the surface varies depending on the local surface slope. The measurement of high slopes as found in microstructures leads to deviations as the probing point no longer lies on the tip’s apex. A probing principle is investigated that applies a surface slope–dependent sensor rotation to reduce measurement deviation by shape superposition. For planning purposes and the determination of the benefit, a simulation of the probing process was performed. Different kinematic chains to rotate the sensor were investigated, and a stacking of two rotary axes was selected. To compensate systematic positioning deviation, a compensation field is applied, acquired by an in situ calibration method. As a basis for the test stand, a nanometer resolution coordinate measuring machine is used and is combined with a near-tactile micro- and nanosensor based on electrical interactions. The test stand has been completed in a preliminary configuration, and the first results are presented.