Title :
Electric properties of an embedded piezoelectric layer
Author :
Köhler, Bernd ; Stauch, Gert
Author_Institution :
Dept. of Acoust. Methods for Nondestructive Evaluation & Quality Assurance, Fraunhofer-Inst. fur Nondestructive Testing, Dresden, Germany
Abstract :
The one-dimensional vibration mode of a piezoelectric layer under different load conditions has been reconsidered. Derived analytical expressions for admittance and impedance at special frequencies are listed. Based on the expressions derived, two applications are proposed involving electrical measurements on a piezoelectric plate. Concerned are first the determination of such plate material parameters which are relevant for its thickness mode of vibration. Difficulties due to spurious vibration modes are avoided in this approach. The second application deals with an alternative determination of acoustic material-impedances otherwise not easily obtainable: a piezoelectric plate is coupled to the material surface by a liquid. The influence of the coupling layer thickness is discussed and a measurement procedure is given by which the detrimental layer thickness effect is minimized.<>
Keywords :
electric admittance measurement; electric impedance measurement; piezoelectric thin films; piezoelectric transducers; vibrations; 1D vibration mode; acoustic material-impedances; admittance; coupling layer thickness; detrimental layer thickness effect; electric properties; electrical measurements; embedded piezoelectric layer; impedance; liquid; load conditions; material surface; measurement procedure; piezoelectric plate; piezoelectric transducers; plate material parameters; special frequencies; thickness vibration mode; Acoustic devices; Acoustic measurements; Acoustic transducers; Impedance; Piezoelectric materials; Piezoelectric transducers; Piezoelectricity; Resonance; Ultrasonic transducers; Vibrations;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
