High-Q microwave acoustic resonators and filters

The authors present recent experimental and modeling results for high-Q microwave acoustic resonators and filters for use in oscillators and other frequency control applications. Overmoded resonators have exhibited an FQ product greater than 1*10/sup 14/ Hz (e.g., Q=68,000 at 1.6 GHz) with a strong inductive response suitable for one-port and two-port oscillator feedback circuits. Ladder filters fabricated with overmoded resonators have loaded Qs greater than 40,000 with 76-kHz bandwidth at 1.6 GHz. Aluminum nitride films were used for transduction on Z-cut sapphire and lithium niobate substrates.<
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