Determination Of Piezoelectric Coefficients Research Articles

Determination of piezoelectric coefficients and elastic constant of thin films by laser scanning vibrometry techniques

Knowledge of the electro-active properties of piezoelectric materials is essential for the modeling and design of novel MEMS devices employing the piezoelectric effect. Cantilevers of piezoelectric thin film on Si were fabricated by using sol–gel and photolithograph wafer processing techniques. A scanning laser vibrometer was used to measure the displacement at the contact pad, the first resonant frequency and the tip deflection of the cantilever. The longitudinal (d33,f), transverse (d31,f) piezoelectric coefficients, and the Young's modulus for the piezoelectric thin films were then determined from these results. Finite element analysis (FEA) modeling was carried out to understand the device behaviors and a good agreement has been found between the measurement and the FEA simulated results.

Contour Modes of Square Plates excited Piezoelectrically and Determination of Elastic and Piezoelectric Coefficients

The suitability of square plates, vibrating in contour modes, for the determination of piezoelectric coefficients is considered. Piezoelectric measurements on such plates provide checks for the theoretical solution of the various modes and in particular for the distribution of displacement. The recently published solutions for square plates form a basis for this work and the reliability of these solutions is discussed. The materials used were sodium chlorate, sodium bromate, quartz, ammonium dihydrogen phosphate and ethylene diamine tartrate (EDT). New determinations of the elastic and piezoelectric coefficients of these materials have been made, with the exception of EDT, the data for which were published in a previous paper