An acoustic wave device includes: a substrate; a pad formed on the substrate; a cap formed of an inorganic insulating material and located on the substrate, the cap including a cavity located in a surface of the cap at a substrate side and a penetration hole formed in a location overlapping with the pad; a terminal filling the penetration hole, coupled to the pad on the substrate, and formed of solder; and a functional element formed on an upper surface of the substrate and in the cavity, the functional element exciting an acoustic wave.

A surface acoustic wave (SAW) filter includes a bottom substrate, a piezoelectric layer disposed above the bottom substrate, the piezoelectric layer having a bottom surface facing the bottom substrate and a top surface opposite to the bottom surface, a lower cavity disposed below the piezoelectric layer, an interdigital transducer (IDT) disposed on the top surface of the piezoelectric layer, and a back electrode disposed on the bottom surface of the piezoelectric layer, and exposed in the lower cavity.

An elastic wave device includes a piezoelectric thin film, IDT electrodes on the piezoelectric thin film, an insulating layer surrounding the piezoelectric thin film on a primary surface of a support substrate, a spacer layer surrounding the piezoelectric thin film in plan view, and a cover on the spacer layer. The spacer layer includes an outer edge and an inner edge closer than the outer edge to the piezoelectric thin film in plan view. The primary surface of the insulating layer closer to the spacer layer includes a sloping region that extends where the insulating layer overlaps the spacer layer in plan view and in which the distance from the first primary surface of the support substrate along the direction perpendicular or substantially perpendicular to the support substrate increases from the outer edge toward the inner edge.

An elastic wave device includes an interdigital transducer electrode, a dielectric film, and a frequency adjustment film are disposed on a LiNbO.sub.3 substrate. When Euler Angles of the LiNbO.sub.3 substrate are within a range of about 0°±5°, within a range of about θ±1.5°, within a range of about 0°±10°, the interdigital transducer electrode includes a main electrode, a film thickness of the main electrode normalized by a wavelength determined in accordance with an electrode finger pitch of the interdigital transducer electrode is denoted as T, and a density ratio of a material of the main electrode to Pt is denoted as r, the film thickness of the main electrode and θ of the Euler Angles satisfy θ=−0.05°/(T/r−0.04)+31.35°.

A surface acoustic wave device assembly includes a collective board, first circuit portions provided on the collective board and respectively including first hot terminals and first ground terminals, a second circuit portion provided on the collective board and including second hot terminals and second ground terminals, and a power supply wiring provided on the collective board so as to surround the periphery of the first circuit portions and the second circuit portion. The first circuit portions include surface acoustic wave devices defining band pass filters. The second circuit portion defines a band pass filter. The first ground terminals and first hot terminals, and the second ground terminal are connected to the power supply wiring, the second hot terminals are not connected to the power supply wiring, and pass bands of the surface acoustic wave devices and a pass band of the band pass filter defined by the second circuit portion are the same or substantially the same.

The invention specifies an electronic component which has a first electrode (10), a second electrode (20), an active region (30), which is electrically coupled to the first electrode (10) and to the second electrode (20), and a housing (100), wherein the housing (100) contains carbon layers which are monoatomic at least in subregions.

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.

A surface acoustic wave filter is disclosed. The surface acoustic wave filter includes a substrate, and first and second surface acoustic wave filter structures disposed on first and second main surfaces of the substrate, respectively. The first surface acoustic wave filter structure includes a first piezoelectric layer a plurality of first surface acoustic wave resonators formed on a top surface of the first piezoelectric layer, and a first wiring layer connecting the first surface acoustic wave resonators to each other. The second surface acoustic wave filter structure includes a second piezoelectric layer, a plurality of second surface acoustic wave resonators formed on a bottom surface of the second piezoelectric layer, and a second wiring layer connecting the second surface acoustic wave resonators to each other. A plurality of through electrodes extends through the substrate, the first piezoelectric layer, and the second piezoelectric layer. A circuit including the first surface acoustic wave resonators and the first wiring layer on the top surface of the first piezoelectric layer forms at least one first radio frequency filter, and a circuit including the plurality of second surface acoustic wave resonators and the second wiring layer on the bottom surface of the second piezoelectric layer forms at least one second radio frequency filter. The at least one first radio frequency filter and the at least one second radio frequency filter belong to different frequency bands.

Acoustic wave devices are disclosed. An acoustic wave device can include a first filter and a second filter coupled to a common node. The second filter includes acoustic wave resonators of a first type (e.g., bulk acoustic wave resonators) and a series acoustic wave resonator of the second type (e.g., a surface acoustic wave resonator) that is coupled between the acoustic wave resonators of the first type and the common node. The acoustic wave device can further include a loop circuit coupled to the first filter, in which the loop circuit is configured to generate an anti-phase signal to a target signal at a particular frequency. In certain embodiments, the first filter is a receive filter and the second filter is a transmit filter.

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.