High-frequency vibration analysis of LiTaO₃ piezoelectric plates excited by lateral electric fields produced by surface electrodes under viscous liquid loadings for sensing

Abstract

In this work, the coupled thickness-shear and flexural vibrations of the LiTaO 3 piezoelectric plates excited by lateral electric fields produced by surface electrodes under viscous liquid loadings are modeled and analyzed based on Mindlin's plate theory. The influences of liquid properties on the admittance characteristics and frequency shifts of the piezoelectric bulk acoustic wave devices operate in the lateral field excitation (LFE) mode are examined. In addition, the effects of the structure parameters, such as the electrode gap width, electrode/plate mass ratio and the electrode width, on the frequency sensitivity are investigated. It is shown that with the increasing electrode/plate mass ratio R, the sensitivities of the device on liquid viscosity and density increase first and then decrease, there is a maximal sensitivity when R is with a certain value. The varying trends of the frequency shifts with various liquid properties and sensitivities with various structural parameters are verified by the FEM simulations. The results are crucial to obtain good vibration characteristics and sensitivities for liquid-phase LFE piezoelectric sensors by using LiTaO 3 piezoelectric crystals.

Evaluation of Elastic Properties and Conductivity of Chitosan Acetate Films in Ammonia and Water Vapors Using Acoustic Resonators

“…These resonators are sensitive to changes in the electrical conductivity and mechanical impedance of the medium in contact with the free side of the resonator, whereas the electrodes are located on the other side of the piezoelectric plate. In particular, the resonators with a lateral electric field have been applied as sensors to assess the viscosity and conductivity of a contacting liquid [9,10]. The effect of the conductivity of a thin layer located near the resonator on its characteristics has also been evaluated [11,12].…”

Recent progress in flexible tactile sensor systems: from design to application

“…However, considering the unique energy collection characteristics of the piezoelectric materials, they have very important advantages in the development of fast dynamic response, low energy consumption, and selfpowered flexible tactile sensors. The piezoelectric materials commonly used in piezoelectric sensors include lead zirconate titanate (PZT) [52][53][54][55][56] , ZnO [57] , BaTiO 3 [58] , LiTaO 3 [59,60] , Group III-nitride (III-N) materials (AlN and GaN) [61][62][63] , and intrinsic flexible polyvinylidene fluoride (PVDF) [64][65][66] .…”

Shear horizontal wave dispersion in two phase magneto-electro-elastic material loaded with viscoelastic fluid layer

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