This paper reviews the basic properties of shear-horizontal (SH)-type surface acoustic waves (SAWs) and bulk acoustic waves (BAWs). As one of the simplest cases, the structure supporting Bleustein-Gulyaev-Shimizu waves is considered, and their excitation and propagation are discussed from various view points. First, the formalism based on the complex integral theory is presented, where the surface is assumed to be covered with an infinitesimally thin metallic film, and it is shown how the excitation and propagation of SH-type waves are affected by the surface perturbation. Then, the analysis is extended to a periodic grating structure, and the behavior of SH-type SAWs under the grating structure is discussed. Finally, the origin of the leaky nature is explained.

Excitation and propagation of shear-horizontal-type surface and bulk acoustic waves

The letter describes theoretical results of the effects of surface metallisation on surface-skimming-bulk-wave (SSBW) and Bleustein-Gulyaev-wave (BGW) propagation characteristics for rotated Y-cuts of quartz. For a range of rotations, the surface metallisation increases the surface mechanical displacement of the BGW relative to the SSBW. The metallisation is ineffective in trapping the SSBW energy close to the surface.

Effects of surface metallisation on SSBW and BGW propagation in quartz

The bibliography published in the Proceedings of the 33rd Annual Symposium on Frequency Control (1979) covers the years 1968 to 1978. The continuation covers articles published or listed in abstract services in 1979 through April 1980. The same selection criteria as last year's have been used.

Precision Frequency Control and Selection a Bibliography, Continued

A spurious response due to bulk waves has often been observed in surface-acoustic filters. This paper shows how bulk waves are radiated by the charge source on the surface of a semi-infinite piezoelectric solid. The expression for each component of bulk waves is evaluated asymptotically, in the form of the Fourier integral, by assuming that the observation point is located far from the source in comparison with a wavelength. In doing this, the method of steepest descents is used in order to integrate analytically. The numerical results are obtained for rotated Y-cut X-propagating LiNbO3 and Y-Z LiNbO3. These results are in good agreement with the experiment reported by Togami and Chiba.

Ken'ichiro Yashiro

Papers

Analysis of bulk waves in surface-acoustic wave devices