Title :
Analysis of the SH wave radiation from the SAW devices
Author :
Matsuda, S. ; Miura, M. ; Matsuda, T. ; Ueda, M. ; Sato, Y. ; Hashimoto, K.
Author_Institution :
Taiyo Yuden Co., Ltd., Akashi, Japan
Abstract :
We prepared SAW resonators using a SiO2/Cu/ 0°YX-LiNbO3 structure. In this configuration, apodized interdigital transducers (IDTs) are commonly adopted for suppressing series of spurious responses caused by the transverse modes. However, the apodization is shown to deteriorates the normalized Q factor at the anti-resonance frequency and its influence grows when the normalized aperture width is narrow. From the optical measurement of these devices, the Q degradation is found to be mainly due to the radiation of SH waves from the resonator. The radiation consists of the bulk, diffraction, and back-scattering waves and depends on the steepness of the apodization.
Keywords :
Q-factor; acoustic imaging; copper; interdigital transducers; lithium compounds; optical images; optical variables measurement; silicon compounds; surface acoustic wave resonators; Q factor; SAW devices; SAW resonators; SiO2-Cu-LiNbO3; apodized interdigital transducers; back-scattering waves; diffraction; normalized aperture width; optical measurement; shear horizontal wave radiation; transverse modes; Apertures; Optical resonators; Optical surface waves; Optical variables measurement; Q factor; Surface acoustic waves; LiNbO3; Q degradation; apodization; optical measurement; radiation of SH waves;
Conference_Titel :
Ultrasonics Symposium (IUS), 2010 IEEE
Conference_Location :
San Diego, CA
Print_ISBN :
978-1-4577-0382-9
DOI :
10.1109/ULTSYM.2010.5935555
