2.97-GHz CVD diamond ring resonator with Q >40,000

A capacitive-gap transduced micromechanical ring resonator based on a radial contour vibration mode and constructed from hot filament CVD boron-doped microcrystalline diamond has achieved a Q of 42,900 at 2.9685GHz that represents the highest series-resonant Q yet measured at this frequency for any on-chip room temperature resonator, as well as the highest f·Q of 1.27×10
¹⁴
for acoustic resonators, besting even macroscopic bulk-mode devices. Values like these in a device occupying only 870μm
²
may soon make possible on-chip realizations of RF channelizers and ultra-low phase-noise GHz oscillators for secure communications.