Reflection and transmission coefficients of SAW in a periodic grating computed by finite element analysis

Author

Bauerschmidt, P. ; Lerch, R. ; Machui, J. ; Ruile, W. ; Visintini, G.

Author_Institution

Inst. fur Hochfrequenztechnik, Erlangen Univ., Germany

fYear

1990

fDate

4-7 Dec 1990

Firstpage

421

Abstract

The finite element method is used to calculate eigenfrequencies of surface acoustic waves (SAW) in an infinite periodic array. With the help of these eigenfrequencies, the approach of D. P. Chen and H. A. Haus (1985) allows the evaluation of reflection and transmission coefficients in a simple manner. Results on the widely used substrates AT-quartz and 128° rot YX-LiNbO are presented. The periodic arrays with period p consist of aluminium electrodes with normalized step heights h/(2p) in the range between 0% and 4%. The influence of trapezoidal electrode shapes is investigated

Keywords

eigenvalues and eigenfunctions; finite element analysis; surface acoustic wave filters; surface acoustic waves; ultrasonic reflection; ultrasonic transmission; AT-quartz; Al electrodes; LiNbO₃; SAW; SAW filter; SiO₂; YX-LiNbO; eigenfrequencies; finite element method; infinite periodic array; normalized step heights; periodic grating; reflection coefficients; transmission coefficients; trapezoidal electrode shapes; Acoustic waves; Electrodes; Finite element methods; Frequency; Gratings; Reflection; Research and development; SAW filters; Surface acoustic wave devices; Surface acoustic waves;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 1990. Proceedings., IEEE 1990

Conference_Location

Honolulu, HI

Type

conf

DOI

10.1109/ULTSYM.1990.171400

Filename

171400