Temperature compensated overtone resonators

Temperature compensated, 15^th-overtone, free-free beam resonators have been demonstrated for use as the timing elements in high performance oscillators. The resonators are designed and fabricated using alternating layers of polysilicon and silicon dioxide such that the opposing temperature coefficients of Young´s modulus in the two materials cancel. The overtone resonator has shown Q´s in excess of 12,000, and the resulting TCf has been reduced from -16ppm/°C to less than -0.1 ppm/°C.