Parallel-beamslever Electrothermal Out-of-plane Actuator

We report on the design, modeling, fabrication and testing of a new electrothermal actuator allowing for various modes of movement and exhibiting large enough forces to be usable in a micro-tribotester. The performance of the actuator has been simulated combiniig numerical and analytical calculations. Experiments have been performed in ambient conditions and vacuum. The theoretical results and measurements are consistent if the temperature dependence of the properties of the polycrystalline Si is taken into account. actuators [2] are used to provide in-plane motion (Tx and Ty translations), necessary for kiction and wear tests. With a parallel plate actuator [3] vertical motion is generated in order to bring the test surfaces into contact and to assure a certain range of normal loads needed to study tribological phenomena in different conditions. The force needed to separate the test surfaces can be as large as hundreds of pN because of adhesion due to extremely smooth surfaces [4]. The novel actuator was designed to be able to provide the range of forces and displacements not only to separate test surfaces but also to measure adhesion strength.