IC-compatible power oscillators using Thin Film Plate Acoustic Resonators (FPAR)

In this study, two-port 880 MHz FPAR devices operating on the lowest order fast symmetric Lamb wave mode (S0) in c-oriented AlN membranes on Si, were fabricated and subsequently tested for their power handling capabilities in a feedback-loop power oscillator circuit. The S0 Lamb waves were excited and detected by a classical two-port resonator structure, as in Rayleigh SAW (RSAW) resonators. Incident power levels of up to 24 dBm (250 mW) for the FPARs were provided by a high-power sustaining amplifier in the loop. No measurable performance degradation was observed. The results from this study indicate that IC-compatible S0 FPAR devices can dissipate orders of magnitude higher RF-power levels than their RSAW counterparts on quartz and are well suited for integrated microwave power oscillators with thermal noise floor (TNF) levels below -175 dBc/Hz.