Stability, Nonlinearity and Reliability of Electrostatically Actuated MEMS Devices

Abstract

Electrostatic micro-electro-mechanical system (MEMS) is a special branch with a wide range of applications in sensing and actuating devices in MEMS. This paper provides a survey and analysis of the electrostatic force of importance in MEMS, its physical model, scaling effect, stability, nonlinearity and reliability in detail. It is necessary to understand the effects of electrostatic forces in MEMS and then many phenomena of practical importance, such as pull-in instability and the effects of effective stiffness, dielectric charging, stress gradient, temperature on the pull-in voltage, nonlinear dynamic effects and reliability due to electrostatic forces occurred in MEMS can be explained scientifically, and consequently the great potential of MEMS technology could be explored effectively and utilized optimally. A simplified parallel-plate capacitor model is proposed to investigate the resonance response, inherent nonlinearity, stiffness softened effect and coupled nonlinear effect of the typical electrostatically actuated MEMS devices. Many failure modes and mechanisms and various methods and techniques, including materials selection, reasonable design and extending the controllable travel range used to analyze and reduce the failures are discussed in the electrostatically actuated MEMS devices. Numerical simulations and discussions indicate that the effects of instability, nonlinear characteristics and reliability subjected to electrostatic forces cannot be ignored and are in need of further investigation.

Nano-opto-electro-mechanical switch based on a four-waveguide directional coupler

“…The bandwidth (extinction ratio > 10dB) of the device is around 50 nm. This 55 nm displacement requirement for switching is well below the pull-in limit (one third of the original distance [31]), and can be made even smaller by adjusting the horizontal gap and device length, but with a loss of bandwidth. The hinges showed in Fig.…”

Survey on Recent Designs of Compliant Micro-/Nano-Positioning Stages

“…The advantages of ESA include high power efficiency, high dynamic performance, and a hysteresis-free input-output relationship [36][37][38]. However, its generated force is relative low, which lies at the nanonewton to millinewton level [11].…”

Harmonic and sub-harmonic resonance of MEMS subjected to a weakly non-linear parametric and external excitations

“…The governing equation of motion for a simplified dynamic system of the micro-cantilever beam in MEMS [18] is represented by the following nonlinear second order differential equation…”