Guided acoustic wave resonators using an acoustic Bragg mirror

Lamb wave devices have recently gained an interest for providing narrow bandpass filters in wireless transmission systems. Their cointegration with film bulk acoustic wave resonators is a major advantage, enabling the possibility to provide simultaneously several radio frequency and intermediate-frequency filters in a single fabrication. Similarly, in this work, we report the fabrication of resonators using waves guided in a piezoelectric layer deposited atop a Bragg mirror. Such waves exhibit a behavior close to Lamb waves, thanks to the acoustic isolation provided by the mirror, while being cointegrated along with solidly mounted resonator structures.