An improved model for the cantilever NEMS actuator including the surface energy, fringing field and Casimir effects

• By considering the modified boundary conditions, the instability of a NEMS electrostatic actuator in precense of Casimir force, and surface energy, is extensively studied.
• The potential energy principle is applied in order to satisfy the equilibrium state in structures subjected to static loading.
• To solve the nonlinear fourth-order boundary value problem, the Duan–Rach method of determined coefficients (MDC) is applied.

The influence of the surface energy on the instability of nano-structures under the electrostatic force has been investigated in recent years by different researchers. It appears that in all prior research, the response of all structures becomes softer due to the surface effects. In the present study, the pull-in instability of a NEMS device incorporating the electrostatic force and Casimir intermolecular attraction for different values of the surface parameter is investigated by the Duan–Rach method of determined coefficients (MDC) in order to identify the remarkable effect of the surface energy. Although the obtained results verify the behavior of such structures in presence of the fringing field and the Casimir attraction same as the previous investigations, however the incremental effects of the surface energy cause the aforementioned structures to behave more stiffly in contrast.

The pull-in instability of a NEMS device incorporating the electrostatic force and Casimir intermolecular attraction for different values of the surface parameter with modified boundary conditions will be investigated.Figure optionsDownload as PowerPoint slide