An electronic module includes a substrate, at least one first electronic component that includes a hollow portion, at least one second electronic component that includes no hollow portion, a first sealing resin, and a second sealing resin. The at least one first electronic component is sealed with the first sealing resin. The at least one second electronic component has a narrowest pitch between the electrodes that are provided on the mounting surface, and at least the mounting surface including the electrodes of the at least one second electronic component are sealed with the second sealing resin. The volume percentage of a filler that is included in the first sealing resin is larger than the volume percentage of a filler that is included in the second sealing resin.

An elastic wave device includes a substrate, an IDT electrode, a spacer layer, a cover, and a protective layer. The spacer layer is provided on the substrate and surrounds the IDT electrode. The cover is provided on the spacer layer, is spaced apart from the IDT electrode, and includes a first main surface adjacent to the spacer layer and a second main surface facing the first main surface. The protective layer includes a third main surface contacting the second main surface, a fourth main surface facing the third main surface, and a side surface connected to the fourth main surface. In at least portion of the side surface of the protective layer, a portion including an intersection line between the side surface and the fourth main surface is located farther inward than an outer edge of the substrate in plan view in the thickness direction of the substrate.

An acoustic wave device includes a substrate, a support portion and a protective member. The substrate has an acoustic wave generator formed on a surface thereof. The support portion is disposed on the surface of the substrate, and includes an accommodating space configured to accommodate the acoustic wave generator. The protective member is coupled to the support portion and disposed to be spaced apart from the acoustic wave generator by a predetermined interval. The protective member is disposed in a seating groove formed in the support portion.

An elastic wave device including a substrate, an interdigital transducer (IDT) electrode provided on an upper surface of the substrate, a first wiring electrode provided on the upper surface of the substrate and connected to the IDT electrode, a dielectric film that does not cover a first region of the first wiring electrode but covers a second region of the first wiring electrode above the substrate, the first wiring electrode including a cutout in the second region, and a second wiring electrode that covers an upper surface of the first wiring electrode in the first region and an upper surface of the dielectric film in the second region above the substrate.

An acoustic wave device includes: a first substrate including a support substrate and a piezoelectric substrate bonded on an upper surface of the support substrate, and including a first acoustic wave element located on an upper surface of the piezoelectric substrate; a ring-shaped metal layer located in a region that surrounds the first acoustic wave element and in which the piezoelectric substrate is removed, a second substrate flip-chip mounted on an upper surface of the first substrate and including a functional element located on a lower surface of the second substrate; and a metallic member located on an upper surface of the ring-shaped metal layer, surrounding the second substrate in plan view, not located between the first substrate and the second substrate, and sealing the first acoustic wave element and the functional element so that the first acoustic wave element and the functional element are located across an air gap.

A composite device includes a silicon substrate including first and second main surfaces on opposite sides, a semiconductor device adjacent to at least one of the first and second main surfaces, and an acoustic wave device including a silicon oxide film directly or indirectly disposed on the first main surface of the silicon substrate, a piezoelectric layer directly disposed on the silicon oxide film, and an IDT disposed on the piezoelectric layer. The piezoelectric layer has a thickness of not greater than about 2.5 where is a wavelength defined by an electrode finger pitch of the IDT.

An electronic module includes a substrate, at least one first electronic component that includes a hollow portion, at least one second electronic component that includes no hollow portion, a first sealing resin, and a second sealing resin. The at least one first electronic component is sealed with the first sealing resin. The at least one second electronic component has a narrowest pitch between the electrodes that are provided on the mounting surface, and at least the mounting surface including the electrodes of the at least one second electronic component are sealed with the second sealing resin. The volume percentage of a filler that is included in the first sealing resin is larger than the volume percentage of a filler that is included in the second sealing resin.

An elastic wave device includes a support substrate and a laminated film disposed on the support substrate. A portion of the laminated film is removed in a region outside a region in which an interdigital transducer electrode is disposed and below a region to which an external connection terminal is joined. An insulating layer is disposed in at least a portion of the region in which the portion of the laminated film is removed. A support layer is disposed on the insulating layer so as to surround the region in which the interdigital transducer electrode is disposed. A main component of a material of which the support layer is made is about 50% or more identical to a main component of a material of which the insulating layer is made. A cover is secured to the support layer to seal a cavity defined by the support layer.

A production method for a surface acoustic wave device comprises the following steps: a step of providing a piezoelectric substrate comprising a transducer arranged on the main front face; a step of depositing a dielectric encapsulation layer on the main front face of the piezoelectric substrate and on the transducer; and a step of assembling the dielectric encapsulation layer with the main front face of a support substrate having a coefficient of thermal expansion less than that of the piezoelectric substrate. In additional embodiments, a surface acoustic wave device comprises a layer of piezoelectric material equipped with a transducer on a main front face, arranged on a substrate support of which the coefficient of thermal expansion is less than that of the piezoelectric material. The transducer is arranged in a dielectric encapsulation layer, between the layer of piezoelectric material and the support substrate.

An elastic wave filter device includes first and second reception filters, an input terminal, output terminals, and reference terminals provided on a piezoelectric substrate. The first reception filter includes series resonators and parallel resonators, and the second reception filter includes series resonators and parallel resonators. The reference terminal connected to the parallel resonator connected so as to be closest to the output terminal among the parallel resonators included in the first reception filter, and the reference terminal connected to the parallel resonator connected so as to be closest to the output terminal among the parallel resonators included in the second reception filter, are separated from each other on the piezoelectric substrate.