Planar ring-shaped phononic crystal anchoring boundaries for enhancing the quality factor of Lamb mode resonators

We report the use of planar ring-shaped phononic crystals (PnCs) as anchor boundaries of very-high-frequency band piezoelectric-on-silicon Lamb moderesonators for the purpose of enhancing their quality factor (Q). Here, we exploit the acousticbandgap associated with the PnC anchoring boundaries to reduce acoustic energy leakage out of the micromechanicalresonator. The proposed approach provides greater mechanical robustness (by merit of interlocking the cells in a matrix) and the possibility of electrical routing through the PnC cells. We experimentally show enhancements inQ by a factor of three using the proposed approach of hybridizing planar ring-shaped PnCs with micromechanicalresonators. The effect of these PnCs onresonatorQ is further corroborated by their effects in suppressing transmission when incorporated into a delay line.

Source: Applied Physics Letters - November 15, 2016 Category: Physics Authors: L. Binci, C. Tu, H. Zhu and J. E.-Y. Lee Source Type: research