Acoustic resonator devices and filters are disclosed. A piezoelectric plate is attached to a substrate, a portion of the piezoelectric plate forming a diaphragm spanning a cavity in the substrate. A first conductor pattern is formed on a surface of the piezoelectric plate. The first conductor pattern includes interleaved fingers of an interdigital transducer disposed on the diaphragm, and a first plurality of contact pads. A second conductor pattern is formed on a surface of a base, the second conductor pattern including a second plurality of contact pads. Each pad of the first plurality of contact pads is connected to a respective pad of the second plurality of contact pads. A seal is formed between a perimeter of the piezoelectric plate and a perimeter of the base.

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.

A method of fabricating an electronic component includes forming a functional unit on a main surface of a substrate, forming a sacrificial layer covering the functional unit on the main surface, forming a cap layer covering the sacrificial layer, the cap layer forming a periphery enclosing the cavity on the main surface, forming holes through the cap layer, forming a cavity by removing the sacrificial layer using a wet etching process through the holes, the holes including a peripheral hole communicating an inside of the cavity with an outside of the cavity along the main surface, and forming a first resin layer covering the cap layer and the main surface.

An electronic component may include a substrate having a functional unit formed on a main surface of the substrate and a first resin layer formed on the main surface, the first resin layer having a first surface facing the main surface and a second surface opposed to the first surface, the first resin layer defining a cavity on the first surface enclosing the functional unit, the first resin layer defining a recess on the second surface, and a solder layer being formed in the recess so as not to exceed the second surface in a thickness direction. The functional unit may include a surface acoustic wave (SAW) element or a film bulk acoustic resonator (FBAR) having a mechanically movable portion. The substrate may be formed of dielectric material.

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 elastic wave device includes a piezoelectric substrate, an IDT electrode, and a cover member. The IDT electrode is provided on the piezoelectric substrate. The cover member is provided above the piezoelectric substrate and separate from the IDT electrode. The cover member includes a first cover member and a second cover member. The second cover member is laminated on a side of the first cover member opposite to the piezoelectric substrate. The glass transition point of the first cover member is higher than that of the second cover member.

An electronic component device includes first and second mount boards, and first, second, and third electronic components. The first electronic component includes a first major surface and a second major surface, and is disposed on the first mount board. The first major surface is positioned closer to the first mount board than the second major surface. The second electronic component includes a third major surface and a fourth major surface, and is disposed on the second mount board. The third major surface is positioned closer to the second mount board than the fourth major surface. The third electronic component includes a fifth major surface and a sixth major surface, and is disposed on the second mount board. The fifth major surface is positioned closer to the second mount board than the sixth major surface. The second major surface directly contacts the fourth and sixth major surfaces, or indirectly contacts the fourth and sixth major surfaces with a bonding layer interposed therebetween.

An electronic component has a support member, an SAW element which is mounted on the support member with a space S therebetween and which has a facing surface which faces the support member, and a resin portion which covers the SAW element and which is provided so as to seal the space S. The SAW element has a piezoelectric substrate, an IDT provided on the facing surface of the piezoelectric board, an wiring (an outer wiring) which is provided on the facing surface of the piezoelectric board and extends from the IDT toward the periphery side of the piezoelectric board, and a dam member which is adjacent to a lateral edge portion of the wiring and which is provided locally relative to the circumferential direction which surrounds the IDT.

An acoustic wave device that utilizes a plate wave includes a recess in an upper surface of a support substrate. A piezoelectric substrate is located on the support substrate with a first principal surface side facing the support substrate. An IDT electrode is provided on the first principal surface of the piezoelectric substrate. The recess defines a cavity that is surrounded by the support substrate and the first principal surface of the piezoelectric substrate. The IDT electrode faces the cavity. The piezoelectric substrate includes through-holes that communicate the cavity and the second principal surface with each other. Sealing materials are filled respectively in the through-holes.

A method for packaging chips includes: providing a filter wafer and a plurality of substrates to be packaged, each substrate to be packaged being provided with one or more first pads; flip-chip bonding the substrates to be packaged on the filter wafer; molding the substrates to be packaged to form a molded layer on the substrates to be packaged, the substrates to be packaged, the molded layer, and the filter wafer forming a molded structure, each substrate to be packaged, a portion of the molded layer formed on the substrate to be packaged, and the filter wafer together enclosing a cavity; exposing the first pads out of the molded layer; and cutting the molded structure into a plurality of particle chips.