The effective resistivity of dissimilar contact materials using an automated MEMS switching test platform

An automated in-situ contact evolution (ICE) apparatus is used to study contact performance for a low contact force (<1 mN) MEMS switching application. The ICE system uses a metrology frame to combine the controlled switching of surfaces with the ability to measure the surface changes in-situ. After a defined number of switching cycles, the surfaces are separated within the metrology frame and measured, then replaced to the same physical location with a precision of 50 nm to continue the switching process. In this study the contact force, resistance relationship is investigated for the evaluation of the effective resistivity of a dissimilar surface combination. In the study a Gold coated hemisphere (radius 1 mm) is used with a Gold Coated (500 nm), multiwalled forest of vertically aligned carbon nanotubes (50 μm), referred to as Au/CNT. In this work we consider the measurement of effective resistivity by the ICE system and 3 other methods, using a nano-indentation system as a reference.