Measurement of BAW radiation from low-loss LSAWresonators

Abstract

The first direct experimental observation of bulk-acoustic wave radiation from a leaky surface-acoustic wave transducer, measured arriving at the backside of the piezoceramic substrate, is reported. A scanning laser-interferometric probe is used to map the spatial distribution of the bulk-wave radiation patterns on the substrate bottom. The different energy-flow angles into the substrate are obtained as functions of frequency and used to identify the corresponding bulkwave modes arriving at the substrate bottom. Programme for Electronic Materials and Microsystems (EMMA), by the Academy of Finland.

Nondiffracting waves in anisotropic media

“…One way of detecting NDWs is the use of interferometric scanning on the back face of the crystal [28,29]. This allows the detection of the surface-normal oscillation with an xy-resolution ≈ 1 µm and amplitude threshold ≈ 0.1 nm.…”