Abstract: A position drive for a wafer in a system for testing of integrated circuit components of the wafer includes a first drive assembly for quick lifting of a wafer-supporting member towards testing probes, second drive assembly for positioning the wafer-supporting member in two stable positions in a vertical direction for compensating thickness allowances of the wafers to be tested and a third drive assembly for mechanical rotation of the wafer-supporting member through any required angle.

Abstract: The invention relates to capacitive probe with a special shielding, in order to be able to measure small differences in distance which correspond to small differences in capacitance.For this purpose, a first and a second electrode are located within a shield which is connected to the ground potential.A coupling pin is located within an opening of the first electrode and, in a given instance, within a recess. A dielectric is placed between the shield, the electrodes and coupling pin, and the dielectric may be divided. The electrodes shield the coupling pin from the shield. The shield has a decoupling projection between the first and second electrodes, so that the capacitances between the first and second electrodes (as well as the capacitance between the shield and the coupling pin) are very small.With the capacitive measuring probe, distances to a conductive material are measured, as well as the position of the bordering edges of the conductive material.

Abstract: The lifting movement of an armature of an electromagnet is braked by means of a gas which flows out under pressure between the abutment faces of a core of the electromagnet and the armature so that the gas is compressed therebetween and discharged in the outer atmosphere.