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 electronic device includes an insulation material layer provided on a first main surface of a piezoelectric substrate and surrounding a functional element, and a protective layer provided on the insulation material layer. The piezoelectric substrate and the insulation material layer define a hollow portion accommodating the functional element. The protective layer includes a first portion above the hollow portion, a second portion adjacent to the first portion at one end of the second portion, and a third portion adjacent to the second portion at another end of the second portion. A distance between the first main surface and a surface of the protective layer in the thickness direction is greatest at a location where the second portion is adjacent to or in a vicinity of the first portion, and the distance is shortest at a location where the second portion is adjacent to or in a vicinity of the third portion.

An electronic structure is provided. The electronic structure includes a substrate, a plurality of conductors, a bump structure, and a protective layer. The conductors are disposed on the substrate. The bump structure is disposed on at least one of the conductors. The protective layer is disposed on the conductors. A region is exposed between the conductors. A method of manufacturing the electronic structure is also provided.

Certain aspects of the present disclosure provide a surface acoustic wave (SAW) resonator with piston mode design and electrostatic discharge (ESD) protections. An example electroacoustic device generally includes a piezoelectric material and a first electrode structure disposed above the piezoelectric material. The first electrode structure comprises first electrode fingers arranged within an active region having a first region and a second region. At least one of the first electrode fingers has at least one of a different width or a different height in the first region than in the second region, and the first electrode fingers comprise a first electrode finger that has a width or height in the second region that is less than a corresponding width or height of the at least one of the first electrode fingers in the second region.

An electroacoustic resonator (EAR) that allows an RF filter having a large bandwidth is provided. The resonator comprises a piezoelectric material (PM) and an electrode structure (ES, EF) on the piezoelectric material. The piezoelectric material is lithium niobate and has a crystal cut defined by the Euler angles (0°, 80° to 88°, 0°).

An electronic device includes an insulation material layer provided on a first main surface of a piezoelectric substrate and surrounding a functional element, and a protective layer provided on the insulation material layer. The piezoelectric substrate and the insulation material layer define a hollow portion accommodating the functional element. The protective layer includes a first portion above the hollow portion, a second portion adjacent to the first portion at one end of the second portion, and a third portion adjacent to the second portion at another end of the second portion. A distance between the first main surface and a surface of the protective layer in the thickness direction is greatest at a location where the second portion is adjacent to or in a vicinity of the first portion, and the distance is shortest at a location where the second portion is adjacent to or in a vicinity of the third portion.

An elastic wave device includes a multilayer film stacked on a support substrate. A first support layer surrounds a region including interdigital transducer electrodes. A second support layer is disposed in the region surrounded by the first support layer. A cover is fixed on the first support layer and the second support layer so as to close a cavity defined by the first support layer. The multilayer film is partially disposed on the support substrate, and an insulating layer is disposed in at least a portion of a region in which the multilayer film is not disposed. At least one of the first support layer and the second support layer is disposed on the insulating layer.

An elastic wave device includes a piezoelectric substrate and an interdigital transducer electrode provided on the piezoelectric substrate. The interdigital transducer electrode includes at least one electrode layer including an outermost electrode layer, and a protective electrode layer protecting the outermost electrode layer, the protective electrode layer has a higher electric resistivity than the outermost electrode layer, the outermost electrode layer includes a first principal surface located at a side opposite to the piezoelectric substrate side, and a side surface connected to the first principal surface, the first principal surface of the outermost electrode layer and a region extending from the first principal surface to at least a portion of the side surface are covered with the protective electrode layer, and the protective electrode layer does not extend beyond a lower edge of the side surface of the outermost electrode layer.

An electro-acoustic resonator comprises a piezoelectric substrate on which an electrode structure is disposed. The electrode structure comprises a metal layer of aluminum and copper, a barrier layer forming a barrier against the diffusion of copper and another metal layer disposed on the barrier layer comprising aluminum. An AlCu intermetallic phase formed after an anneal is restricted to the portion beneath the barrier layer so that Galvano-corrosion of the electrode structure is avoided.

An electronic device includes a support layer is provided on a piezoelectric substrate and surrounds a functional element. A cover layer is located above the support layer, and faces the piezoelectric substrate. A protective layer seals the support layer and the cover layer. The support layer is provided on at least the outer periphery of the piezoelectric substrate, and defines a hollow portion within the outer periphery of the piezoelectric substrate. The protective layer includes a first portion above the hollow portion, a second portion above the support layer, and a curved surface that is convex in an opposite direction from the piezoelectric substrate.