TEMPERATURE-COMPENSATED FILM BULK ACOUSTIC RESONATOR (FBAR) DEVICES

摘要

The temperature-compensated film bulk acoustic resonator, FBAR, device (100) comprises an FBAR stack (111). The FBAR stack comprises an FBAR (110) and a temperature-compensating element (109). The FBAR is characterized by a resonant frequency having a temperature coefficient, and comprises opposed planar electrodes (112, 114) and a piezoelectric element (116) between the electrodes. The piezoelectric element has a temperature coefficient on which the temperature coefficient of the resonant frequency depends at least in part. The temperature compensating element has a temperature coefficient opposite in sign to the temperature coefficient of the piezoelectric element.