Optimal T-support anchoring for bar-type BAW resonators

This paper reports on an optimal support anchoring for bar-type BAW resonators. We demonstrate both theoretically and experimentally the implementation of long (in terms of acoustic wavelength) T-supports without compromising neither on the Q-factor nor on the electromechanical (pull-in) stability of the resonator. Compared to the more common straight supports, these long T-supports provide rigidity for displacements in one direction combined with low stiffness in the other two directions, thus offering more freedom in the structural design, as well as potential for thermal “manipulation”, e.g., insulation.