7MHZ length-extensional soi resonators with T-shaped anchors

This paper presents the performance of differentially-driven 7 MHz length-extensional bulk-mode resonators using T-shaped and straight-beam anchors. Resonators with T anchor results in lower motional resistance and higher quality factor of about 717,680 which is six times higher than that achieved for straight-beam anchor. However, it was observed that the length-extensional resonance mode is dependent on the geometry of the T anchor, that is, at certain dimensions for the T structure, the T anchor significantly hinders the length-extensional mode of resonator. Differential drive of two adjoining resonators, which are normally two-port extensional-mode resonators, effectively removes parasitic feedthrough capacitances that usually suppress the transmission response.