High velocity pseudo surface waves (HVPSAW)

Author

Da Cunha, Mauricio Pereira ; Adler, Eric L.

Volume

1

fYear

1994

fDate

Oct. 31 1994-Nov. 3 1994

Firstpage

281

Abstract

Current interest in low-loss UHF filters for use in mobile and personal communication systems has led to a number of pseudo-SAW (PSAW) and SH mode based SAW devices. These filters can operate at higher frequencies than SAW-based ones for a given line-width because PSAW and SH mode velocities can be significantly higher than corresponding SAW velocities. Furthermore for certain orientations the attenuation of the PSAW is acceptably small. In this paper the existence of an independent high-velocity pseudo-SAW (HVPSAW) mode is discussed. The HVPSAW is shown to have a phase velocity close to the longitudinal bulk wave velocity and to be quasi-longitudinally polarized. The nature of this HVPSAW mode is described for both electrically open-circuited and layered metallic short-circuited conditions for several piezoelectric materials. Numerical and experimental data are presented which discuss the existence and properties of these high-velocity pseudo surface waves

Keywords

UHF filters; piezoelectric materials; quartz; surface acoustic wave filters; ultrasonic velocity measurement; SiO₂; high velocity pseudo surface waves; longitudinal bulk wave velocity; low-loss UHF filters; mode velocities; open-circuited conditions; phase velocity; piezoelectric materials; pseudo-SAW devices; quartz; quasi-longitudinally polarized; short-circuited conditions; Acoustic velocity measurement; Piezoelectric materials/devices; Quartz materials/devices; Surface acoustic wave filters; UHF filters;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 1994. Proceedings., 1994 IEEE

Conference_Location

Cannes, France

Print_ISBN

0-7803-2012-3

Type

conf

DOI

10.1109/ULTSYM.1994.401595

Filename

401595