Transient Analysis on Nonlinear Model of Electrostatically Actuated Nanomechanical Switch

I.K. Kim, D.H. Han and S.I. Lee
University of Seoul, KR

Keywords: carbon nanotube, nano-switch, nonlinear modeling


This research predicted the transient behaviors of a nano-switch with static and dynamic analysis. The nano-switch consists of a cantilevered MWCNT incorporating the electrostatic forces and intermolecular attractive and repulsive forces between the CNT and graphene ground plane. To design the stable on-off switching in dynamic range is very important to predict the contact bounce at pull-in. To investigate the transient pull-in/out behaviors with large deflection of the CNT and different excitation frequency, our model includes geometric and inertial nonlinearities of the CNT. To solve this problem, we used the Galerkin discretization method and the numerical time integration technique. As a result, we calculated the static pull-in/out voltages using the minimum potential energy profiles. We identified that the nonlinear effect of CNT affects the pull-in/out behaviors calculating near the pull-in/out voltages with linear and nonlinear model. The nonlinear model had the lower pull-in voltage and higher pull-out voltage than those of the linear model. The contact bounce prevented the perfect pull-in when the nano-switch was switched quickly. On the pull-out behaviors, the amplitude had twice as much as the gap. This shows that the packaging margin in nano-switch device would be needed more than twice of the gap.