An electroacoustic device includes, stacked in a direction a silicon-based substrate, a first electrode, a piezoelectric layer with the basis of a perovskite taken from among lithium niobate LiNbO3, lithium tantalum LiTaO3, or an Li(Nb,Ta)O3 alloy, on the first electrode, a second electrode disposed on the piezoelectric layer. Advantageously, the first electrode is made of a nitride-based electrically conductive refractory material, such as TiN, VN, TaN. The invention also relates to a method for producing such a device.

A solidly mounted resonator having an electromagnetic shielding structure and a method for manufacturing the same. The solidly mounted resonator includes: a substrate; an acoustic-wave reflecting layer formed on the substrate; a resonance function layer formed on the acoustic-wave reflecting layer; and a metal shielding wall formed on the substrate, wherein the metal shielding wall surrounds an effective region in the acoustic-wave reflecting layer and the resonance function layer. The electromagnetic shielding structure is formed simultaneously with the resonator, and it is not necessary to provide an additional electromagnetic shielding device. An influence of an external or internal electromagnetic interference source on the resonator is avoided while ensuring a small dimension and a high performance of the resonator.

An integrated circuit (IC) resonator module for an IC package includes an acoustic resonator having a surface and a Bragg reflector adhered to the surface of the acoustic resonator. The Bragg reflector includes low impedance layers formed of a first material with a first acoustic impedance and a high impedance layer formed of a second material with a second acoustic impedance. The second acoustic impedance is greater than the first acoustic impedance. The Bragg reflector further includes a Bragg grating layer formed of randomly or periodically spaced patches of the second material separated by vias filled with the first material.

A method for manufacturing an acoustic device includes providing a substrate, providing a bottom electrode over the substrate, providing a sacrificial layer on the bottom electrode, patterning the bottom electrode and the sacrificial layer, polishing the sacrificial layer such that a portion of the sacrificial layer remains on the bottom electrode, and removing the remaining portion of the sacrificial layer via a cleaning process such that a surface roughness of the bottom electrode is maintained. By performing the polishing such that a portion of the sacrificial layer remains on the bottom electrode and subsequently removing that portion of the sacrificial layer via a cleaning process that maintains the surface roughness of the bottom electrode, the subsequent growth of a piezoelectric layer on the bottom electrode can be substantially improved.

A method of forming a resonator structure can be provided by forming one or more template layers on a substrate, (a) epitaxially forming an AlScN layer on the template layer to a first thickness, (b) epitaxially forming an AlGaN interlayer on the AlScN layer to a second thickness that is substantially less than the first thickness, and repeating operations (a) and (b) until a total thickness of all AlScN layers and AlGaN interlayers provides a target thickness for a single crystal AlScN/AlGaN superlattice resonator structure on the template layer.

An elastic wave device includes a supporting substrate including an upper surface including a recessed portion, a piezoelectric thin film on the supporting substrate to cover the recessed portion of the supporting substrate, an IDT electrode on a main surface of the piezoelectric thin film, the main surface being adjacent to the supporting substrate, and an intermediate layer on a main surface of the piezoelectric thin film, the main surface being remote from the supporting substrate. A space is defined by the supporting substrate and the piezoelectric thin film. The IDT electrode faces the space. Through holes are provided in the piezoelectric thin film and the intermediate layer to extend from a main surface of the intermediate layer to the space, the main surface being remote from the piezoelectric thin film. The elastic wave device further includes a cover member on the intermediate layer and covering opening ends of the through holes.

A bulk acoustic wave resonator includes: a first electrode; a piezoelectric layer disposed on at least a portion of the first electrode; and a second electrode disposed on the piezoelectric layer. The piezoelectric layer contains a dopant, and a value of [a thickness (nm) of the piezoelectric layer×a concentration (at %) of the dopant]/100 is less than or equal to 80.

An acoustic wave device includes: a substrate; a first electrode on the substrate; a piezoelectric layer on the first electrode; and a second electrode on the piezoelectric layer. A bonding interface is located between the substrate and the first electrode. The full width at half maximum (FWHM) in the X-ray diffraction pattern of the crystal plane <002> of the piezoelectric layer is between 10 arc-sec and 3600 arc-sec.

In at least one embodiment, the electric component comprises a first BAW-resonator (1), a second BAW-resonator (2) electrically connected to the first BAW-resonator and a carrier substrate (3) with a top side (30) on which the BAW-resonators are arranged. The first and the second BAW-resonator each comprise a bottom electrode (11,21) and a top electrode (12,22). The bottom electrodes are in each case located between the carrier substrate and the respective top electrode. A first piezoelectric layer (13) is arranged between the top electrode and the bottom electrode of the first BAW-resonator and laterally protrudes from the first BAW-resonator. The second BAW-resonator is mounted on the first piezoelectric layer in a region laterally next to the first BAW-resonator and comprises a second piezoelectric layer (23) between its top electrode and its bottom electrode. The two piezoelectric layers may have different thickness to realize resonators with different resonance frequencies on the same die.

Methods of fabricating resonator and filter devices. A first conductor pattern formed on a front surface of a piezoelectric plate includes a first plurality of contact pads and an interdigital transducer (IDT). The IDT and the piezoelectric plate are configured such that a radio frequency signal applied to the IDT excites a shear primary acoustic mode within the piezoelectric plate. An acoustic Bragg reflector is between a substrate and a back surface of the piezoelectric plate, the acoustic Bragg reflector configured to reflect the shear primary acoustic mode. A second conductor pattern including a second plurality of contact pads is formed on a back surface of the interposer. The first plurality of contact pads is directly connected to respective contact pads of the second plurality of contact pads. A perimeter of the acoustic resonator chip is sealed to a perimeter of the interposer.