Title

Simulation of short LSAW transducers including electrode mass loading and finite finger resistance

Authors

Authors

K. J. Gamble;D. C. Malocha

Abbreviated Journal Title

IEEE Trans. Ultrason. Ferroelectr. Freq. Control

Keywords

INTERDIGITAL TRANSDUCERS; SAW; Acoustics; Engineering, Electrical & Electronic

Abstract

The theory for the 2-D numerical analysis of acoustic wave generation from finite length leaky surface acoustic wave (LSAW) transducer structures is presented. The mass loading of the electrodes is incorporated through the use of the finite element method (FEM). The substrate is modeled using both analytical and numerical means. The advantages of this simulation are twofold. First, it is capable of extracting the individual bulk wave conductances from the overall conductance of a given device. At large distances from the transducer, the angular distribution of power radiated relative to the substrate surface can then be calculated for each of the three possible bulk wave polarizations. The second advantage of the simulation is that the effect of finite electrode resistance is included through the use of a series equivalent resistance for each electrode in the structure. Once the resistance for each electrode in the structure has been determined, the overall effect on the device admittance is modeled by applying a constrained minimization process to the electrical boundary conditions of the transducer. To conclude the paper, the simulation will be compared against the experimental admittance of a 37-finger uniform transducer with a metalization ratio of 0.5 on 42degrees LiTaO3. The agreement between theory and experiment is excellent.

Journal Title

Ieee Transactions on Ultrasonics Ferroelectrics and Frequency Control

Volume

49

Issue/Number

1

Publication Date

1-1-2002

Document Type

Article

Language

English

First Page

47

Last Page

56

WOS Identifier

WOS:000173531300007

ISSN

0885-3010

Share

COinS