Resonator and filter devices and methods of fabrication. A resonator chip includes a substrate, a piezoelectric plate, and an acoustic Bragg reflector between the substrate and a back surface of the piezoelectric plate. A conductor pattern on a front surface of the 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. The acoustic Bragg reflector is configured to reflect the shear primary acoustic mode. An interposer has a second plurality of contact pads on a back surface. A seal connects a perimeter of the piezoelectric plate to a perimeter of the interposer. Each contact pad of the first plurality of contact pads is directly connected to a respective contact pad of the second plurality of contact pads.

An acoustic wave resonator package includes an acoustic resonator comprising an acoustic wave generator on a surface of a substrate, a cover member disposed over the acoustic wave generator, a bonding member, disposed between the substrate and the cover member, to bond the substrate and the cover member to each other, and a wiring layer, disposed along surfaces of the cover member, connected to the acoustic resonator. Among the surfaces of the cover member, bonding surfaces to which the bonding member and the wiring layer are bonded at least partially have a roughness Rz in a range of 70 nm to 3.5 .Math.m.

An acoustic resonator filter includes: a series member including a plurality of series acoustic resonators electrically connected between a first radio frequency (RF) port and a second radio frequency port; and a shunt member including one or more shunt acoustic resonators electrically connected between the series member and a ground, wherein the plurality of series acoustic resonators are disposed to be anti-parallel to each other, and at least a portion of the first RF port includes a first connection via and a second connection via extending in a direction different from a direction in which the first connection via and the second connection via face the plurality of series acoustic resonators.

Close-contact layers that are capable of improving the degree of contact between electrodes and a ceramic insulating layer can be formed at low cost by firing a glass paste. When the electrodes, the ceramic insulating layer, and the close-contact layers are fired at the same time, the glass paste is sintered last, and thus, formation of voids, defects, and the like in portions of the ceramic insulating layer, on which the electrodes are disposed, as a result of shrinkage of the electrodes and the ceramic insulating layer at the time of firing being hindered by stress generated due to the difference in the degree of shrinkage can be suppressed. Therefore, the structure of the ceramic insulating layers in the above portions can be elaborated by the close-contact layers.

A resonator element includes a substrate having a first region performing thickness shear vibration, a second region located in a periphery of the first region and having a smaller thickness than the first region, a fixed end, and a free end opposite to the fixed end in the first region in a plan view. Excitation electrodes are disposed on a front and a rear of the first region and have regions overlapping each other in the plan view. A center of the first region and a center of the regions overlapping each other are located between a center of the substrate and the free end in the plan view. When Cs is a distance between the center of the regions overlapping each other and the center of the substrate in the plan view, a relation of 105 μm<Cs<130 μm is satisfied.

An improved electro acoustic RF filter (FC) is provided. The RF filter comprises an electro acoustic resonator (EAR) connected between an input port and an output port, an impedance element and a damping and/or dissipation element (DE) in mechanical contact to the impedance element. The damping and/or dissipation element is provided and configured to remove acoustic energy from the impedance element which has a similar construction as the resonator on the same substrate. With such a construction an acoustically inactive impedance element (AIIE) is obtained.

The present disclosure relates to a Wafer-level-packaged Bulk Acoustic Wave (BAW) device, which includes a bottom electrode, a top electrode, a top electrode lead, a piezoelectric layer sandwiched between the bottom and the top electrodes, an enclosure, and an anti-reflective layer (ARL). Herein, an active region for a resonator is formed where the bottom electrode and the top electrode overlap. The top electrode lead is over the piezoelectric layer and extending from the top electrode. The enclosure includes a cap and an outer wall that extends from the cap toward the piezoelectric layer to form a cavity. The top electrode resides in the cavity and a first portion of the outer wall resides over the top electrode lead. The ARL, with a reflectance less than 40% R, is between the first portion of the outer wall and the top electrode lead.

An acoustic wave device includes: a substrate; an acoustic wave generating part disposed on a surface of the substrate; a ground pad disposed on the surface of the substrate; a support part spaced apart from the acoustic wave generating part on the surface of the substrate; a shielding member disposed on the support part, and spaced apart from the acoustic wave generating part; and a ground terminal disposed on the ground pad, wherein the ground pad and the shielding member are electrically connected to each other through the ground terminal.

The disclosure is directed to an electronic device with a solder interconnect and multiple material encapsulant. The electronic device includes a die last assembly with the die assembled to an electronic packaging substrate by a solder interconnect. At least a portion of a first dielectric material and the die are milled or ground, with a second dielectric material applied over an exposed portion of the die. A shield is then positioned over and electrically insulated from the die. Accordingly, such a configuration reduces a thickness or height of an electronic device with shielding and a die last assembly.

An electronic device includes: a first substrate including a first functional element located on an upper surface of the first substrate; a second substrate that is flip-chip mounted on the upper surface of the first substrate through a bump, and includes a second functional element located on a lower surface of the second substrate; and a sealing member that is located on the upper surface of the first substrate, surrounds the second substrate in plan view, is not located between the first substrate and the second substrate, seals the first functional element and the second functional element so that the first functional element and the second functional element are located across an air gap.