Embodiments of this application provide a filter and a method for adjusting performance of a filter, so as to quickly adjust performance of a filter. The filter includes at least two acoustic wave resonators; and a performance adjustment structure, connected to an output end of a first acoustic wave resonator and an input end of a second acoustic wave resonator, where the first acoustic wave resonator and the second acoustic wave resonator are any two of the at least two acoustic wave resonators, the performance adjustment structure includes a capacitor structure and/or an inductor structure, and the performance adjustment structure is configured to adjust an energy coupling mode between the first acoustic wave resonator and the second acoustic wave resonator.

A surface acoustic wave device is disclosed. The surface acoustic wave device can include a multilayer piezoelectric substrate having a support substrate and a piezoelectric layer over the support substrate. The piezoelectric layer has a first surface facing the support substrate and a second surface opposite the first surface. The surface acoustic wave device can include an interdigital transducer electrode having a first portion and a second portion. The first portion is positioned below the second surface of the piezoelectric layer and the second portion is positioned above the second surface. The first portion has a first sidewall and a second portion has a second sidewall angled relative to the first sidewall.

An improved DMS filter with electrode structures between a first port and a second port is provided. Wiring junctions are realized in multilayer crossing with dielectric material in between. There are insulating patches (L2) between crossing conductor layers (L1,L3). Signal wirings may be realized with multiple conductor layers (L1, L3) to reduce wiring resistance and the upper conductor layer (L3) of the signal wiring may partly overlap the insulating patches (L2). The insulating patches (L2) may extend over the acoustic path to achieve temperature compensation.

A filter device includes at least one first acoustic wave resonator and at least one second acoustic wave resonator. The at least one first acoustic wave resonator includes a first piezoelectric substrate and first and second IDT electrodes. The first piezoelectric substrate includes a piezoelectric layer with first and second main surfaces facing each other. The first IDT electrode is on the first main surface. The second IDT electrode is on the second main surface and faces the first IDT electrode. The at least one second acoustic wave resonator includes a second piezoelectric substrate and a third IDT electrode. The second piezoelectric substrate includes a piezoelectric layer with third and fourth main surfaces facing each other. The third IDT electrode is on one of the third and fourth main surfaces.

An elastic wave device includes a supporting substrate, an acoustic reflection layer on the supporting substrate, a piezoelectric layer on the acoustic reflection layer, and an IDT electrode on the piezoelectric layer. The acoustic reflection layer includes three or more low-acoustic impedance layers and two or more high-acoustic impedance layers. At least one of a first relationship in which in which, a film thickness of a first low-acoustic impedance layer closest to the piezoelectric layer is thinner than a film thickness of a low-acoustic impedance layer closest to the first low-acoustic impedance layer, and a second relationship in which a film thickness of a first high-acoustic impedance layer closest to the piezoelectric layer is thinner than a film thickness of a high-acoustic impedance layer closest to the first high-acoustic impedance layer, is satisfied.

Aspects and embodiments disclosed herein include an acoustic wave device comprising a substrate, a pair of inter-digital transducer (IDT) electrodes formed on the substrate, each of the pair of IDT electrodes including a bus bar and a plurality of fingers extending from the bus bar, fingers of one IDT electrode arranged interleaved with fingers of the other IDT electrode, each of the bus bars of the pair of IDT electrodes having a slotted portion configured on an upper surface of the bus bars opposite to a lower surface contacting the substrate such that at least one hollow within each of the bus bars is opened at least at the upper surface of each of the bus bars, and a dielectric film covering the pair of IDT electrodes, at least a portion of the dielectric film filling in the at least one hollow of each of the bus bars.

A surface acoustic wave (SAW) device is provided with a piezoelectric substrate, an interdigitated transducer (IDT), and multiple dielectric layers. The IDT is over a top surface of the piezoelectric substrate and comprises first and second electrodes with interdigitated fingers. A first higher k dielectric layer is provided over the IDT, and a first lower k dielectric layer is provided over the first higher k dielectric layer. The dielectric constant of the first higher k dielectric layer is higher than the dielectric constant of the first lower k dielectric layer.

A surface acoustic wave device is disclosed. The surface acoustic wave device can include a first interdigital transducer electrode that is in electrical communication with a first piezoelectric layer and a second interdigital transducer electrode that is in electrical communication with a second piezoelectric layer. The first and second interdigital transducer electrodes are positioned between at least a portion of the first piezoelectric layer and at least a portion of the second piezoelectric layer. The first and second interdigital transducer electrodes are positioned such that the second interdigital transducer electrode is configured to transduce a wave generated by the first interdigital transducer electrode. The first interdigital transducer electrode can be an input interdigital transducer electrode, and the second interdigital transducer electrode can be an output interdigital transducer electrode.

Surface acoustic wave (SAW) structures with transverse mode suppression are disclosed. In one aspect, the SAW structure provides digits or fingers with broad interior terminal end shapes. By providing such shapes spurious modes above the resonance frequency of the SAW are suppressed thereby providing desired out of band rejection that helps satisfy design criteria such as keeping a higher Q value, a higher K2 value and better Temperature Coefficient of Frequency (TCF).

Surface acoustic wave (SAW) structures with transverse mode suppression are disclosed. In one aspect, the SAW structure provides digits or fingers with broad interior terminal end shapes. By providing such shapes, spurious modes above the resonance frequency of the SAW are suppressed, thereby providing desired out-of-band rejection that helps satisfy design criteria such as keeping a higher Q value, a higher K2 value, and a better Temperature Coefficient of Frequency (TCF).