A 586 MHz microcontroller compensated MEMS oscillator based on ovenized aluminum nitride contour-mode resonators

This work reports on the demonstration of a Microcontroller Compensated MEMS Oscillator based on a UHF ovenized AlN CMR, which shows temperature stability, short-term stability, and acceleration sensitivity comparable to SAW-based oscillators. Over the temperature range -25 ÷ 85°C, the demonstrated 586 MHz oscillator exhibits a temperature stability of 1.7 ppm, stable phase noise values better than -91 dBc/Hz at 1 kHz, and -160 dBc/Hz at 40 MHz offsets, and acceleration sensitivity values better than 30 ppb/g. The design of the integrated heater all-around the top RF electrodes and the new digital temperature controller allowed to simplify the fabrication process compared to our previous demonstration, and to virtually compensate frequency shifts of any origin, i.e. from both the MEMS and the electronic circuitry.