Experimental study of phase noise in FBAR resonators.

Phase noise of micromachined bulk acoustic wave resonators is investigated. A measurement bench, able to characterize the phase noise of a single resonator on-wafer, is set up. The experimental data demonstrate the existence of a 1/f phase noise component, the amplitude of which is strongly dependent on the resonator geometry. Particularly, the apodized resonators have shown the best phase noise performance, with no degradation of the Q factor.