A torque sensor chip including a semiconductor substrate, an acoustic reflector formed on the semiconductor substrate, and first and second Lamb wave resonators (LWRs). The first LWR is formed on a side of the acoustic reflector opposite the semiconductor substrate. The first LWR is at a first angle with respect to an axis of the IC. The second LWR also is formed on the side of the acoustic reflector opposite the semiconductor substrate. The second LWR is at a second angle, different than the first angle, with respect to the axis of the IC.

A surface acoustic wave resonator device comprises a substrate supporting: a gateable, electrically conducting layer; an interdigital transducer (IDT); a reflector grating that comprises a plurality of electrically separated fingers; a main ohmic contact; and a gate element. The IDT is configured to be connectable to a ground. The conducting layer is configured to be connectable to the ground via the main ohmic contact, while each of said fingers is electrically connected to a lateral side of the conducting layer. This defines a gateable channel, which extends from the fingers to the ground via the conducting layer and the main ohmic contact. The gate element is electrically insulated from the conducting layer. The gate element is configured to allow an electrical impedance of the gateable channel to be continuously tuned by applying a voltage bias to this gate element with respect to the ground, in operation of the device.

Certain aspects of the present disclosure provide an electroacoustic device and methods for signal processing via the electroacoustic device. One example electroacoustic device generally includes a first surface acoustic wave (SAW) resonator comprising a first apodized interdigital transducer (IDT) disposed between a first busbar and a second busbar, and a second SAW resonator comprising a second apodized IDT disposed between the second busbar and a third busbar, wherein the second busbar is at an angle with respect to at least one of the first busbar or the third busbar.

An elastic wave device includes an interdigital transducer electrode, a dielectric film, and a frequency adjustment film are disposed on a LiNbO.sub.3 substrate. When Euler Angles of the LiNbO.sub.3 substrate are within a range of about 0° ± 5°, within a range of about θ ± 1.5°, within a range of about 0° ± 10°, the interdigital transducer electrode includes a main electrode, a film thickness of the main electrode normalized by a wavelength determined in accordance with an electrode finger pitch of the interdigital transducer electrode is denoted as T, and a density ratio of a material of the main electrode to Pt is denoted as r, the film thickness of the main electrode and θ of the Euler Angles satisfy θ = -0.05°/(T/r - 0.04) + 31.35°.

Interdigital transducer (IDT) and reflective structure arrangements for surface acoustic wave (SAW) devices are disclosed. Representative SAW devices are described herein with reduced overall size while maintaining good quality factors. In certain embodiments, a SAW device may include an IDT arranged between reflective structures on a piezoelectric material. The reflective structures may include reflective IDTs that are configured to have a phase difference with the IDT to reflect and confine acoustic waves in the piezoelectric material. In certain embodiments, the reflective structures may be electrically connected to at least one of an input signal or an output signal. In this manner, the reflective structures may be configured with reduced size as compared to conventional reflective structures such as gratings, thereby providing a SAW device with reduced dimensions without a negative impact on device performance.

An elastic wave device includes a piezoelectric substrate, IDT electrodes disposed on the piezoelectric substrate, a first wiring line, an insulating layer covering at least a portion of the first wiring line, a second wiring line at least a portion of which is disposed on the insulating layer to provide a three-dimensional crossing portion, a peripheral support including a cavity surrounding the IDT electrodes, the first and second wiring lines, and the insulating layer, a partition support disposed in the cavity, and a cover disposed on the peripheral support and the partition support to cover the cavity. The second wiring line includes a step portion electrically connecting a portion of the second wiring line located on the piezoelectric substrate and a portion of the second wiring line located on the insulating layer to each other. The partition support covers the step portion.

A multiplexer includes a first filter disposed between an antenna common terminal and a first terminal, and a second filter that is disposed between the antenna common terminal and a second terminal and that has higher passband frequencies than the first filter. The second filter includes IDTs that are longitudinally coupled. Among IDT electrodes in the IDTs, first IDT electrodes are connected to the antenna common terminal side, and second IDT electrodes are connected to the second terminal side. The first and second IDT electrodes have different main pitches of the electrode fingers. At least one of the second IDT electrodes out of all of the electrode fingers has a maximum main pitch.

An elastic wave device includes an interdigital transducer electrode, a dielectric film, and a frequency adjustment film are disposed on a LiNbO.sub.3 substrate. When Euler Angles of the LiNbO.sub.3 substrate are within a range of about 0°±5°, within a range of about θ±1.5°, within a range of about 0°±10°, the interdigital transducer electrode includes a main electrode, a film thickness of the main electrode normalized by a wavelength determined in accordance with an electrode finger pitch of the interdigital transducer electrode is denoted as T, and a density ratio of a material of the main electrode to Pt is denoted as r, the film thickness of the main electrode and θ of the Euler Angles satisfy θ=−0.05°/(T/r−0.04)+31.35°.

A filter includes: a piezoelectric substrate; one or more series resonators that are located on the piezoelectric substrate and are connected in series between an input terminal and an output terminal; at least one series resonator that is connected between a first node and a second node, is included in the one or more series resonators, and includes a reflector that is grounded, the first node and the second node being located between the input terminal and the output terminal; and a cancel line that is connected in parallel with the at least one series resonator between the first node and the second node, and cancels a signal outside a passband propagating through the at least one series resonator from the first node to the second node.

A high-frequency device includes: a circuit substrate including dielectric layers that are stacked, wiring patterns located on at least one of the dielectric layers, and a passive element formed of at least one of the wiring patterns, the circuit substrate having a first surface that is a surface of an outermost dielectric layer in a stacking direction of the dielectric layers; a terminal for connecting the high-frequency device to an external circuit, the terminal being located on the first surface and electrically connected to the passive element through a first path in the circuit substrate; and an acoustic wave element located on the first surface and electrically connected to the passive element through a second path in the circuit substrate.