A Low Jitter Monolithic MEMS Thin Film SAW Oscillator in $0.13 \mu \mathrm{m}$ CMOS

The design and measurement of a monolithic low-jitter thin-film surface-acoustic-wave (TFSAW) based oscillator employing an integrated micro-electromechanical systems (MEMS) SAW resonator developed on top of a standard $0.13-\mu \mathrm{m}$ CMOS technology [1] are presented. All oscillator circuitry is placed under the SAW resonator for efficient area utilization enabling a compact low-cost highly-integrated solution. The oscillator has an oscillation frequency of 323 MHz and power dissipation of 10.5 mW. Measured phase noise performance of the oscillator is −121 dBc/Hz at 10-kHz offset frequency and measured noise floor is a −146 dBc/Hz. The integrated phase jitter from 12 kHz to 20 MHz is less than 160 fs. For a lower power consumption of 5 mW, the phase noise performance is −118 dBc/Hz at 10-kHz offset frequency, −142 dBc/Hz noise floor, and the integrated phase jitter is 212 fs. This performance allows the development of highperformance low-jitter highly-integrated low-cost clocking solutions based on MEMS SAW oscillators replacing traditional quartz crystal and SAW-based discrete solutions.