Batch-fabricated high Q-factor microcrystalline diamond cylindrical resonator

This paper reports a 1.5 mm batch-fabricated polycrystalline diamond Cylindrical Resonator (CR) for gyroscope applications. The device is fabricated in a cylindrical shape using silicon on insulator (SOI) wafers and deep reactive ion etching (DRIE), which allows flexibility of choosing different geometries and materials for the resonator structure. A quality factor (Q) of 313,100 is measured at the 23 kHz 2 theta elliptical wineglass modes, producing a ring-down time of 4.32 seconds. Annealing CRs at 700 °C in a nitrogen atmosphere improved Q from 75,000 to over 300,000. The highly symmetric fabrication results in CRs with an excellent frequency mismatch of 3 Hz (130 ppm) between the 2 theta degenerate wineglass modes without applying any tuning voltage.