Capillary condensation and quantum vacuum effects on the pull-in voltage of electrostatic switches with self-affine rough plates

Abstract

Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Palasantzas, G. (2006). Capillary condensation and quantum vacuum effects on the pull-in voltage of electrostatic switches with self-affine rough plates. Journal of Applied Physics, 100(5), art. -054503.[054503]. DOI: 10.1063/1.2229937 Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons).Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. In this work, we study the influence of capillary forces in combination with electrostatic and quantum vacuum generated forces on the pull-in voltage of microswitches having self-affine rough surfaces. This type of roughness is described by the rms roughness amplitude w, the in-plane correlation length , and the roughness exponent H that quantifies the degree of surface irregularity at short length scales ͑Ͻ ͒. It is shown that an attractive capillary force decreases more the effective pull-in voltage when the plate surfaces are rougher. The latter corresponds to smaller roughness exponents H and/or larger long wavelength roughness ratios w / . Notably, the capillary contribution increases the sensitivity of the effective pull-in voltage on the roughness exponent H. This behavior takes place for values of H close to its experimental accuracy.

Switch on, switch off: stiction in nanoelectromechanical switches

“…Interestingly, (16) . These results may be summarized in a regime diagram illustrating the parameter ranges for which each of the two contact (or adhesion) transitions occur -see figure 5, bottom.…”

Contact angle influence on the pull-in voltage of microswitches in the presence of capillary and quantum vacuum effects

“…14,16 Recently, we studied the influence of capillary forces in combination with electrostatic and quantum vacuum generated forces on the pull-in voltage of microswitches having self-affine rough surfaces. 19 It was shown that the attractive capillary force decreases more the effective electrostatic pull-in voltage when the plate surfaces are rougher. The latter corresponds to smaller roughness exponents H ͑0 Ͻ H Ͻ 1, which characterize short wavelength roughness͒ and/or larger long wavelength roughness ratios w / with w the root-mean-square ͑rms͒ roughness amplitude and the in-plane correlation length.…”

“…The latter corresponds to smaller roughness exponents H ͑0 Ͻ H Ͻ 1, which characterize short wavelength roughness͒ and/or larger long wavelength roughness ratios w / with w the root-mean-square ͑rms͒ roughness amplitude and the in-plane correlation length. 19 Therefore, since capillary forces can strongly influence the operation of microswitches, the influence of the capillary meniscus contact angle on the pull-in potential will be further investigated. Indeed, up to now we have not presented any detailed investigation of the influence of the contact angle on pull-in characteristics for rough plate surfaces.…”

“…[9][10][11][12][13] Recent studies for switches with rough plates have shown that random self-affine roughness, which often occurs during nonequilibrium film deposition, strongly influences pull-in parameters and phase maps of microswitches in the presence of electrostatic, Casimir, and capillary forces. 18,19 Furthermore, MEMSs/NEMSs are fabricated on silicon substrates by deposition and selective etching of multiple layers of structural and sacrificial films. 14 If the resulting surface is hydrophilic, a capillary force develops when the microstructures are pulled out of water or when two surfaces approach each other in humid environments causing adhesion between components.…”

Pull-in voltage of microswitch rough plates in the presence of electromagnetic and acoustic Casimir forces

“…[9][10][11][12][13] Recent studies for switches with rough plates have shown that random selfaffine roughness, which often occurs during nonequilibrium film growth, strongly influence pull-in parameters of microswitches in presence of electrostatic, Casimir, and capillary forces. 18,19 Besides EM vacuum fluctuations which induce an attractive Casimir force, 15 Larraza 20 transferred this idea into acoustics and measured the force between two parallel plates in an external sound field with a bandwidth from 5 to 20 kHz. 20 In the space between the two plates, lowerfrequency modes were suppressed leading to an attractive force.…”