Deformable Carbon Nanotube-Contact Pads for Inertial Microswitch to Extend Contact Time

Abstract

We have demonstrated a batch-fabricated inertial microswitch with extended contact time using carbon nanotube (CNT)-contact pads. Self-assembled and aligned CNT bundles, as deformable electromechanical contact pads are selectively synthesized on fully fabricated single crystal silicon microstructures. Outstanding mechanical flexibility and resilience, as well as electrical conductivity of CNTs, make them suitable as an electromechanical contact material. It is experimentally verified that the elastic deformation of CNTs dramatically enhances the contact time of the inertial microswitch from 7.5 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu\hbox{s}$</tex></formula> to 114 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu\hbox{s}$</tex></formula> . Due to the prolonged contact time, the presented inertial microswitch provides reliable and easy detection of threshold acceleration, which is crucial in diverse commercial applications such as airbag restraint systems in vehicles or geriatric healthcare systems.