High resolution laser-interferometric probing of SAW devices

Author

Knuuttila, Jouni ; Tikka, Pasi ; Thorvaldsson, Thor ; Hashimoto, Ken-Ya ; Salomaa, Martti M.

Author_Institution

Mater. Phys. Lab., Helsinki Univ. of Technol., Espoo, Finland

Volume

1

fYear

1998

fDate

1998

Firstpage

235

Abstract

Measurements on the surface-acoustic wave profiles in various SAW devices have been performed with a scanning laser interferometer. SAW profiles at frequencies up to 1 GHz are obtained with our interferometer. Fast automatic computer control enables high-resolution scans with a large number of measuring points at speeds up to 10 000 points/hour. Our interferometer can detect below one Angstrom vibrations of the surface. These capabilities have been utilized to scan modern SAW devices. The SAW beam in a SPUDT filter has been studied. In addition, a new acoustic loss mechanism has been detected in SAW resonators operating at 1 GHz via probing an IEF filter. Our measurements serve to unfold the direct connection between the acoustic losses present at selected frequencies and the corresponding increased insertion loss of the filter at these frequencies

Keywords

acoustic variables measurement; light interferometry; surface acoustic wave filters; surface acoustic wave resonators; 1 GHz; IEF filter; SAW resonator; SPUDT filter; acoustic loss; computer control; high resolution probe; insertion loss; scanning laser interferometry; surface acoustic wave device; vibration measurement; Acoustic devices; Acoustic measurements; Acoustic signal detection; Frequency; Performance evaluation; Resonator filters; Surface acoustic wave devices; Surface acoustic waves; Surface emitting lasers; Surface waves;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 1998. Proceedings., 1998 IEEE

Conference_Location

Sendai

ISSN

1051-0117

Print_ISBN

0-7803-4095-7

Type

conf

DOI

10.1109/ULTSYM.1998.762135

Filename

762135