LIGA-microtesting system with integrated strain gauges for force measurement

A microsystem is presented which is applied in bending experiments of cantilever microbeams to determine the Young's modulus of electroplated materials used in the LIGA-process. The microsystem is manufactured by the LIGA technology [1] combined with a sacrificial layer [2] technique and the sacrificial structure [3] technique. The system consists of a pneumatically driven microactuator, an optical position sensor, and a unit for specimen fixing (Fig. 1). Strain gauges are integrated in the force transmitting unit of the actuator - a movable piston - for direct measurement of the forces transmitted to the specimen. The actuator allows to transmit forces of several 10 mN and displacements of 100 mu m and more. In this way, the first LIGA-made microsystem has been realized which combines a fluid driven microactuator with electrical and optical sensors for force and displacement measurement.