Title :
Optimized Stoneley wave device by proper choice of glass overcoat
Author :
Irino, Toshio ; Shimizu, Yasutaka
Author_Institution :
Basic Res. Lab., NTT, Tokyo, Japan
fDate :
3/1/1989 12:00:00 AM
Abstract :
The characteristics of a Stoneley wave propagated along an interface between a piezoelectric material and an isotropic material were investigated both theoretically and experimentally. First, the condition for the existence of Stoneley waves was shown for various piezoelectric materials. A rule of thumb for selecting the combination of the two materials was obtained. Then, LiTaO/sub 3/ was selected as the piezoelectric material and SiO/sub 2/ was selected the isotropic material. After the calculation of the Stoneley wave characteristics, actual devices were fabricated and measured. The experimental results were found to be in good agreement with the theory; zero slope temperature and high electromechanical coupling coefficient (K/sup 2/=1.5%) were obtained for Stoneley wave propagation between SiO/sub 2//X-148 degrees LiTaO/sub 3/. As a result, future surface-acoustic-wave (SAW) devices can be made without any package.<>
Keywords :
lithium compounds; silicon compounds; surface acoustic wave devices; LiTaO/sub 3/; SAW; SiO/sub 2/; Stoneley wave device; electromechanical coupling; glass overcoat; interface; isotropic material; piezoelectric material; slope temperature; surface-acoustic-wave; Acoustic propagation; Electronics packaging; Glass; Packaging machines; Piezoelectric materials; Substrates; Surface acoustic waves; Temperature; Thumb; Zinc oxide;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
