Integrated micro S.A.W. resonator using longitudinal perturbations

A micro SAW (surface acoustic wave) resonator has been developed which is suitable for integrated acoustics applications because it overcomes size limitations associated with conventional resonators. Analytical expressions are presented for incident and reflected fields in a periodically perturbed acoustic waveguide resonator, based on a corrugated waveguide of a given length in a grating configuration. Based on these calculations, two kinds of devices were developed and tested: (1) a corrugated waveguide filter and (2) microresonator structured. In addition experimental results are presented on microresonator devices on conventional YZLiNbⁿO₃. A guided micro-resonator enables one to reduce the transducers' size since its energy should be focused to a narrow waveguide. This size reduction along with focusing by an acoustic lens confines the incident acoustic waves to the waveguides and enables integration of several elements on one crystal surface. This virtual insulation avoids crosstalk distortions between unwanted signals.