The present invention relates to the field of
microelectronics technology, and in particular to a high-order
acoustic wave filter and a
communication device using the same. The high-order
acoustic wave filter provided by the present invention includes at least one series
resonator and at least one parallel
resonator; the
resonator in the high-order
acoustic wave filter includes a supporting substrate, a bottom
electrode, a piezoelectric film and a top
electrode arranged in sequence from bottom to top; the top
electrode is a forked electrode; the target mode of the resonator is a high-order acoustic
wave mode generated by excitation of a longitudinal
electric field; by making the product of the electrode finger spacing of the top forked electrode of some resonators and the anti-
resonance frequency greater than the slow shear wave sound velocity of the supporting substrate, and making all resonators meet the product of the electrode finger spacing of the forked electrode and the upper
cutoff frequency of the filter less than the fast shear wave sound velocity of the supporting substrate, it is possible to not only reduce the influence of the
parasitic mode of the resonator, but also ensure that the
passband of the filter is almost unaffected.