A High-$Q$ Widely Tunable Gigahertz Electromagnetic Cavity Resonator

This paper describes the design, fabrication and testing of a quasi-static electromagnetic cavity resonator fabricated using potassium-hydroxide (KOH) etching, shallow reactive-ion etching (RIE), metalization and wafer bonding. The resonator is distinguished by its simultaneous high-Q near 200, and wide high-frequency tuning range, 2.5-4.0 GHz for the experimental resonator presented here. When combined with an integrated actuator, it should be suitable for use in electronically tunable radio-frequency (RF) bandpass filters and oscillators. The experimental resonator, however, is tuned with an external piezoelectric actuator for simplicity