AHIGH-STABILITYMEMS FREQUENCY REFERENCE

Silicon MEMS resonators withhighlevels offrequency stability aredemonstrated inan oscillator systemsuitable for use as a frequency reference. Theuseofresonator quality factor (Q)as a temperature sensorallows ustocontrol thetemperature oftheresonator withmilli-degree precision, thus stabilizing theoutputfrequency oftheresonator to-0.1 ppm. Composite Si/SiO2 resonator design has reduced theinherent frequency sensitivity oftheresonator. Thecombination ofQ(T)temperature stabilization andcomposite resonator design hasreduced thefrequency variation to-0.01 ppm, a level that iscompetitive withhigh-performance commercial devices.