Tomasz L. Klosowiak

A static technique for the electro-mechanical characterization of MEMS devices for RF and microwave applications

Abstract : An approach for measuring force-dependent properties of microscopic structures commonly found in MEMS has been developed. The system has the capability of measuring forces and deflections on the order of micro-newtons and micro-meters, respectively. By implementing a visual inspection system, force can be selectively applied to localized areas on a beam, and the resulting force-deflection characteristic obtained from which beam stiffness and effective elastic modulus can be calculated. These results were compared to simulation, which was performed using ANSYS FEM code. In addition, by applying a known mechanical force, direct correlation to voltage and thus electrostatic force can be obtained, which also elucidates the magnitude of the electrostatic feedback effect. Characterization of other force-dependent parameters such as contact resistance at DC, in addition to isolation/insertion loss at RF and microwave frequencies was obtained experimentally from which parameters such as lumped capacitance and inductance can be extracted.