Design, fabrication and characterization of piezoelectric micro-cantilever operated in liquid environment for ultrasound energy source applications

Hynix semiconductor, Icheon, Korea
Microsystem Technologies (Impact Factor: 0.88). 08/2011; 17(8):1319-1327. DOI: 10.1007/s00542-011-1292-0


This paper presents a resonant-driving piezoelectric micro-cantilever for application to the ultrasound source, which can
provide sufficient ultrasound energy in liquid environment by actuating maximally at the cantilever’s resonant frequency.
The compact-sized micro-cantilevers were firstly designed to be operated in deionized water solution in this paper with consideration
of its further application to intravascular catheter-delivered transducer-tipped ultrasound thrombolysis devices as the ultrasound
energy source. The micro-cantilever models, which have the target resonant frequencies of ~40kHz in DI water, were designed
on the basis of numerical calculations, finite element method analysis and pre-experiment results based on the measured resonant
frequencies in air, and fully fabricated by micromachining technologies. The resonant frequencies in DI water for each cantilever
model were measured to be 10.94, 23.14, 33.1, and 44.02kHz which are matched excellently with the targeted frequencies of
10, 20, 30 and 40kHz, respectively. In addition, we could experimentally observe that red blood cells aggregated locally
in 5% diluted blood solution were rapidly disaggregated within a few seconds by sufficient ultrasound energy generated by
resonant-actuations of the proposed micro-cantilever.

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