Response of quartz crystal resonators possessing a superhydrophobic surface

Paul Roach, Chris Evans, Neil Shirtcliffe, Glen McHale, Michael Newton

Research output: Chapter in Book/Report/Conference proceedingChapter

2 Citations (Scopus)

Abstract

A quartz crystal resonator immersed in a water-glycerol solution has a systematically reducing resonant frequency and an increase in bandwidth of the resonance as the concentration of glycerol increases. This behavior is well-known and is accurately described by the Kanazawa and Gordon model, which provides a clear proportionality to the square root of the density-viscosity product of the mixture. It is also well-known that a hydrophobic surface having high aspect ratio protrusions can become superhydrophobic so that the liquid no longer retains contact with all points on the surface. In such a situation for a quartz crystal surface, it is expected that a decoupling of the acoustic wave will occur and the response may not then conform to the Kanazawa and Gordon model. In this work, we report on the behavior of quartz crystal resonators fabricated with 5-18 micron tall micro-post structures both before and after they have been treated with a fluorochemical to make them hydrophobic. We report contact angle data showing that the hydrophobic surfaces are super-repellent for the entire range of water-glycerol mixtures. We obtain and fit the impedance spectra to the Butterworth-van-Dyke model and show, in this extreme case, a complete change in acoustic response occurs. The impedance spectra show a rich mixture of behavior including resonances that become sharper as the concentration of glycerol increases and surfaces showing a decoupling of the acoustic wave response.
Original languageEnglish
Title of host publication2007 IEEE International Frequency Control Symposium Joint with the 21st European Frequency and Time Forum
Place of PublicationPiscataway
PublisherIEEE
Pages587-590
Number of pages4
ISBN (Print)978-1-4244-0646-3
DOIs
Publication statusPublished - 2007
Event2007 IEEE International Frequency Control Symposium Joint with the 21st European Frequency and Time Forum, FCS - Geneva, Switzerland
Duration: 29 May 20071 Jun 2007

Conference

Conference2007 IEEE International Frequency Control Symposium Joint with the 21st European Frequency and Time Forum, FCS
CountrySwitzerland
CityGeneva
Period29/05/071/06/07

Fingerprint Dive into the research topics of 'Response of quartz crystal resonators possessing a superhydrophobic surface'. Together they form a unique fingerprint.

Cite this