Temperature compensated solidly mounted bulk acoustic wave resonators with optimum piezoelectric coupling coefficient

We propose a new way to temperature compensate solidly mounted bulk acoustic wave resonators (SMRs). With the proposed process high Q, high electromechanical coupling coefficient, fully temperature compensated resonators have been successfully fabricated with TCF less than 1 ppm/°C and total thermal drift of less than 35 ppm across the temperature range from 0-100°C.