Microscope stage with magnetic positioningThehard-magnetic CoSm layers (cobalt samarium) developed at the Fraunhofer IST in Braunschweig are applied to non-magnetic metal strips, giving them a defined magnetic structure or functional layer that can be encoded with a signal pattern and read out by a sensor in order to determine their position. These tapes are used in the microscope stages of Dr. ITK Kassen GmbH. In combination with sensors and an evaluation algorithm, they significantly increase the positioning accuracy of the microscope stage on which the sample is placed for observation. The coatings enable positions to be approached with an accuracy of up to five nanometers. Repeat accuracies of plus/minus 100 nm can be achieved. This is particularly important when examining living objects, where examination time is often short and rapid positioning is therefore essential.
The coatings replace galvanic cobalt coatings, which require environmentally harmful chemicals for deposition. They are characterized by their robustness and durability as well as their particularly good magnetic properties: They enable a stronger magnetic signal and non-contact measurement. They can also be used to measure in closed components such as hydraulic cylinders, which optical systems cannot reach. CoSm coatings are produced using a technology developed at the IST, hollow cathode gas flow sputtering, a vacuum coating process. Unlike galvanic processes, no harmful substances are used here.
Pictures: ITK Dr. Kassen GmbH
