An acoustic wave device with a bent section is disclosed. The acoustic wave device includes a piezoelectric layer and an interdigital transducer electrode on the piezoelectric layer. The bent section is arranged to create a curvature in a waveguide of the acoustic wave device to suppress a transverse spurious mode of the acoustic wave device.

According to one configuration, an acoustical device includes a piezoelectric substrate and at least one curved electrode. Material on a surface of the piezoelectric substrate defines boundaries of a resonance region. The curved electrode is disposed on the piezoelectric substrate in the resonance region and is operable to receive a voltage input signal through a first conductive waveguide. When present, the voltage input signal causes generation and conveyance of acoustical waves from the curved electrode into the resonance region. The acoustical device optionally includes a second curved electrode in the resonance region, which converts the acoustical waves present in the resonance region to an output voltage signal.

Phase shift circuits including two or more slanted-finger IDT electrodes, and filters, duplexers, or other electronic devices incorporating same. In one example a filter includes a main filter circuit connected between an input and an output and having a first phase characteristic, and a phase shift circuit connected in parallel with the main filter circuit, the phase shift circuit including first and second capacitor elements and a pair of acoustic wave elements connected in series between the first and second capacitor elements, the pair of acoustic wave elements including a pair of slanted-finger IDT electrodes disposed apart from each other on a single acoustic wave path along which acoustic waves propagate through the acoustic wave elements, the phase shift circuit having a second phase characteristic opposite to the first phase characteristic in an attenuation band that corresponds to at least a portion of a stopband of the main filter circuit.

An acoustic wave device includes acoustic wave resonators each including a piezoelectric substrate including a piezoelectric body layer, and an IDT electrode on the piezoelectric substrate and including electrode fingers. At least one of the acoustic wave resonators is an excitation angle change resonator, in which, the piezoelectric body layer includes a propagation axis and the electrode fingers are curved. In the excitation angle change resonator, an excitation direction of an acoustic wave in a portion of one of the electrode fingers is one of first, second, or third directions. An excitation angle of the excitation angle change resonator is not uniform in the IDT electrode.

A filter working with surface acoustic waves comprises a piezoelectric substrate (SU), a first transducer (IDT1) arranged in the acoustic track coupled to an input, having a first mean finger period (pi) assigned to a center frequency of a pass band of the filter and a second transducer (IDT2) arranged in the acoustic track coupled to an output, having the same first mean finger period (p1), and a reflector arranged between first and second transducer having a second mean finger period (p2) assigned to a stop band frequency different from the center frequency. Further, a new type of very broad bandwidth filters with small insertion loss and high return loss and high rejection are given that use a substrate that can propagate a PSAW and comprises fan shaped transducers.

An acoustic wave device includes: a piezoelectric substrate; and an IDT formed on the piezoelectric substrate, wherein an anisotropy coefficient is positive, an overlap region where electrode fingers of the IDT overlap each other includes a center region and an edge region, the electrode fingers in the center and edge regions are continuously formed, the electrode finger in the edge region is inclined with respect to the electrode finger in the center region so that a pitch in a width direction of the electrode finger in the edge region is greater than a pitch in a width direction of the electrode finger in the center region, and an angle between the width direction in the center region and a crystal axis orientation of the piezoelectric substrate is less than an angle between the width direction in the edge region and the crystal axis orientation.

An acoustic wave device includes a piezoelectric layer and an IDT electrode. The IDT electrode includes first and second busbars, and first and second electrode fingers interdigitated with each other. A virtual line connecting ends of the second electrode fingers is defined as a first envelope, a virtual line connecting ends of the first electrode fingers is defined as a second envelope, and a region between the first and second envelopes is an intersection region. Shapes of the first and second electrode fingers include at least two curved portions different from each other in the intersection region. In the intersection region, a value of at least one of a duty ratio, an electrode finger pitch, and thicknesses of the first and second electrode fingers changes in one of a direction in which the value increases and the direction in which the value decreases.

Described herein are techniques for enhancing isolation in on-chip piezoelectric-based isolators. Several techniques are described that improve isolation in piezoelectric isolators. According to an aspect of the present disclosure, a piezoelectric isolator may include structures arranged to decrease the occurrence of pockets of high electric field and/or to increase the breakdown electric field in the path from the transmitter to the receiver. Further aspects of the present disclosure relate to techniques for increasing the efficiency of piezoelectric isolators while also limiting the formation of spurious signals. The inventors have developed techniques for promoting propagation of surface acoustic waves toward the receiver while limiting propagation in the opposite direction.

Described herein are techniques for enhancing isolation in on-chip piezoelectric-based isolators. Several techniques are described that improve isolation in piezoelectric isolators. According to an aspect of the present disclosure, a piezoelectric isolator may include structures arranged to decrease the occurrence of pockets of high electric field and/or to increase the breakdown electric field in the path from the transmitter to the receiver. Further aspects of the present disclosure relate to techniques for increasing the efficiency of piezoelectric isolators while also limiting the formation of spurious signals. The inventors have developed techniques for promoting propagation of surface acoustic waves toward the receiver while limiting propagation in the opposite direction.

An acoustic wave device includes a piezoelectric substrate including a piezoelectric layer, and resonator electrodes on the piezoelectric substrate and each including electrode fingers and an IDT electrode. The resonator electrodes include first and second resonator electrodes. At least one of the first and second resonator electrodes includes a curved resonator electrode in which the electrode fingers have a curved shape in plan view. The first and second resonator electrodes face each other, and a resonator electrode is positioned on a convex side, in a direction in which the electrode fingers are arranged, of a portion including the curved shape of the curved resonator electrode.