Regularized Model of Post - Touchdown Configurations in Electrostatic MEMS : Bistability Analysis

This paper considers the problem of stiction in electrostatic-elastic deflections whereby elastic surfaces adhere to one another after coming into physical contact under attracting Coulomb interactions. This phenomenon is studied in a family of recently derived models which account for forces which become important when the elastic surfaces are in close proximity. The presence of bistability in these models results in hysteresis, or non reversibility, which accounts for the difficulty in achieving separation after an initial contact event. We use singular perturbation techniques to derive explicit formula for the critical parameters over which bistability occurs and discuss new operational modes which arise when bistability is present.