Title :
Determination of elastic constants of thin films by dispersion of various SAW modes
Author :
Makarov, S. ; Chilla, E. ; Fröhlich, H.J.
Abstract :
For the determination of the mechanical properties of thin films the inverse problem of the surface acoustic wave (SAW) propagation has to be solved by using the phase velocity dispersion for input data. We have analysed the numerical solution of the inverse problem by calculating a two-dimensional error field of least-squares fits. The shape of the error field is a function of arbitrary elastic parameters with respect to their exact values. Various isotropic films deposited on Y-cut LiNbO3 were considered. It was found that by the use of the dispersion of two independent SAW modes the elastic parameters of an isotropic thin film can be determined with high accuracy
Keywords :
elastic constants; inverse problems; least squares approximations; surface acoustic waves; thin films; ultrasonic velocity; LiNbO3; SAW mode dispersion; Y-cut LiNbO3 substrate; elastic constants; elastic parameters; inverse problem; isotropic films; least-squares fits; mechanical properties; numerical solution; phase velocity dispersion; surface acoustic wave propagation; thin films; two-dimensional error field; Acoustic propagation; Acoustic waves; Data analysis; Gold; Inverse problems; Mechanical factors; Polarization; Surface acoustic waves; Transistors; Velocity measurement;
Conference_Titel :
Ultrasonics Symposium, 1995. Proceedings., 1995 IEEE
Conference_Location :
Seattle, WA
Print_ISBN :
0-7803-2940-6
DOI :
10.1109/ULTSYM.1995.495598
