Localized-mass sensors using thin-film bulk acoustic resonators (FBAR) have been implemented for the study of sensitivity and possible configurations in biological applications. In a first experiment, a group of resonators are loaded with the same amount of mass but different contact areas, achieving responsivities as high as 10-19 g/Hz, and potential sensitivities in the order of 10-14 g. These numbers are at least one order of magnitude higher than those obtained for uniform thin-film loadings, although it is clear that sensitivity decreases with the area of the localized-mass. The current phase-noise levels and the quality factor of resonators would allow measuring frequency changes of 30 kHz - the minimum measured frequency shifting has been 500 kHz so far - due to a mass deposition of 9.0 × 10-15 g. In a second experiment, localized-loadings with the same mass are located in different positions of the top electrodes of the corresponding FBARs. It was found out that a location change of the mass in the electrode causes different magnitudes of frequency shifting. A discussion on these topics is opened, in order to define future applications and research lines concerning localized-mass sensing in FBARs. © 2007 Elsevier B.V. All rights reserved.
|Journal||Sensors and Actuators, A: Physical|
|Publication status||Published - 10 Mar 2008|
- Mass sensors
- Responsivity and sensitivity of sensors
- Thin-film bulk acoustic wave resonators
Campanella, H., Uranga, A., Romano-Rodríguez, A., Montserrat, J., Abadal, G., Barniol, N., & Esteve, J. (2008). Localized-mass detection based on thin-film bulk acoustic wave resonators (FBAR): Area and mass location aspects. Sensors and Actuators, A: Physical, 142, 322-328. https://doi.org/10.1016/j.sna.2007.05.004