A large Out-of-plane Motion Microcantilever Driven by Small In-plane Actuation

A new actuation mode for out-of-plane motion is proposed here, which is realized by converting the in-plane force into the out-of-plane deflection. We hope to apply this new actuation mode on the cantilever aimed at a versatile instrument for in situ combination of scanning probe microscopy and time-of-flight mass spectrometry. Through the incorporation of this actuation, this cantilever is endowed with large deflection and ultra big slope at the free end of the lever arm, as well as pure single crystal silicon property exclusion of any types of thin film deposition. The in-plane movement is driven by electrostatic driven comb-drive actuators. The improved comb-drive actuators here apply the new structure consisting of asymmetrical one set of moving fingers and two sets of fixed fingers structure. This unique design allows both actuation and feedback to serve for cantilever deflection. The elastic deflection mechanism of the cantilever is gotten by both theoretical and simulation results. The effect of hinge on the bigger deflection is proved by comparison. It also shows a big cantilever deflection can be achieved by only a comparatively small comb-drive actuators stroke.