DocumentCode :
3463389
Title :
Temperature derivatives of elastic stiffness evaluated from the SAW delay-temperature behavior on lithium tantalate plates
Author :
Kozlov, A.S. ; Taziev, R.M. ; Vasiliev, L.L. ; Yakovkin, L.B.
Author_Institution :
Inst. of Semicond. Phys., Acad. of Sci., Novosibirsk, Russia
Volume :
1
fYear :
1995
fDate :
7-10 Nov 1995
Firstpage :
393
Abstract :
The paper presents an accurate evaluation of the temperature derivatives of elastic stiffness of lithium tantalate on SAW delay-temperature dependence data. We use a nonlinear formalism to correct describing SAW propagation on X,Y-cuts of lithium tantalate plates subjected to homogeneous thermally-induced deformation. A least squares method is used to fit the temperature derivatives of the elastic constants of lithium tantalate to the measured SAW temperature coefficients of delay of the first order (TCD1). To decrease computation time, the perturbation procedure is employed. This allows us to fit optimally the constants of crystals in order to get the coincidence with experimental SAW delay-temperature data using only one iteration step. To measure the SAW temperature coefficients of delay we used a new high-sensitivity method. The measurement errors of TCDI are better than 0.15%. The sensitivity ofthe method is about 0.01%
Keywords :
delays; elastic constants; iterative methods; least squares approximations; lithium compounds; surface acoustic wave devices; surface acoustic waves; LiTaO3; SAW delay-temperature behavior; computation time; elastic constants; elastic stiffness; high-sensitivity method; homogeneous thermally-induced deformation; iteration step; least squares method; nonlinear formalism; perturbation procedure; Crystalline materials; Crystals; Equations; Least squares methods; Lithium compounds; Propagation delay; Surface acoustic waves; Temperature dependence; Temperature measurement; Time measurement;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Ultrasonics Symposium, 1995. Proceedings., 1995 IEEE
Conference_Location :
Seattle, WA
ISSN :
1051-0117
Print_ISBN :
0-7803-2940-6
Type :
conf
DOI :
10.1109/ULTSYM.1995.495605
Filename :
495605
Link To Document :
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