Mechanical stability and adhesion of microstructures under capillary forces. I. Basic theory

Influence of random roughness on the adhesion between metal surfaces due to capillary condensation

“…Dispersive surface forces ͑e.g., van der Waals/Casimir͒, which are relatively well understood, 1,2 contribute to adhesion and play a major role during the fabrication and operation of MEMS. [3][4][5][6][7][8] However, complications arise when dealing with real systems due to surface roughness and capillarity driven forces.…”

Tensionless contact of a finite beam: Concentrated load inside and outside the contact zone

“…For a finite [1,2] or an infinite beam [5,6] with zero gap distance from its contacting substrate, this assumption is always true. However, for a finite beam with a nonzero gap distance [3,4,7], this assumption may not hold. For example, when a nanoindenter indents a micro-cantilever, which is modeled as a concentrated load applied to a beam, the concentrated load is shown to be outside the contact zone [4].…”

“…The contact problem of a flexural structure is encountered in the indentation of such onedimensional nanostructures as nanobelt [1] and nanowire [2], or in the stiction of microcantilever [3,4]. An implicit assumption of the previous works on the tensionless contact of a beam or a plate is that the concentrated load is within…”

Nonlinear oscillation of nanoelectro-mechanical resonators using energy balance method: considering the size effect and the van der Waals force

“…In nanoscale, the influence of the van der Waals attractions on the behavior of the actuator becomes significant when the separation space between the electrode and the substrate is very small (typically in separation spaces below 20 nm) (Mastrangelo and Hsu 1993). The van der Waals attraction is a function of the material properties and is proportional to the inverse cubic power of the separation space (Soroush et al 2012;Farrokhabadi et al 2013;Koochi et al 2013;Sedighi and Daneshmand 2014).…”