Rigorous treatment of leaky SAWs and new equivalent circuit representation for interdigital transducers

Author

Hikita, Mitsutaka ; Isobe, Atsushi ; Sumioka, Atsushi ; Matsuura, Naoki ; Okazaki, Katsunori

Author_Institution

Central Res. Lab., Hitachi Ltd., Tokyo, Japan

Volume

43

Issue

3

fYear

1996

fDate

5/1/1996 12:00:00 AM

Firstpage

482

Lastpage

490

Abstract

Leaky surface acoustic wave (SAW) interdigital transducers (LDTs) formed on 36/spl deg/ YX-LiTaO/sub 3/ and 41/spl deg/ and 64/spl deg/ YX-LiNbO/sub 3/ are theoretically analyzed, and a new equivalent circuit representation is proposed. The influence of the attenuation constant due to leakage as well as conductance caused by bulk wave radiation are taken into account. A new treatment based on an integral equation approach provides all circuit parameters. Fundamental experiments show fairly good agreement between theoretical and experimental results, confirming that this treatment provides very accurate tools for designing leaky-SAW devices.

Keywords

Green´s function methods; electric impedance; equivalent circuits; interdigital transducers; lithium compounds; surface acoustic wave filters; surface acoustic wave resonator filters; surface acoustic wave transducers; surface acoustic wave waveguides; transmission line matrix methods; LiNbO/sub 3/; LiTaO/sub 3/; SAW resonator; SAW waveguide; YX-cut substrates; attenuation constant; bulk wave radiation; characteristic impedance; circuit parameters; conductance; dyadic Green´s function; equivalent circuit representation; integral equation approach; interdigital transducers; leaky SAW; leaky-SAW device design; resonator-coupled filters; transmission line equations; transversal filter; trial function; Acoustic transducers; Acoustic waves; Equivalent circuits; Integral equations; Land mobile radio cellular systems; SAW filters; Surface acoustic waves; Surface treatment; Tensile stress; Transmission lines;

fLanguage

English

Journal_Title

Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on

Publisher

ieee

ISSN

0885-3010

Type

jour

DOI

10.1109/58.489408

Filename

489408