A doubts rotated quart/crystal resonator comprises a cantilever-mounted doubts rotated resonating element having a line of geometrical symmetry running from a supported end to a free end which is not perpendicular to the resonating element's crystallographic/axis. A method of manufacturing the crystal resonator comprises cutting a doubly rotated quartz crystal plate with x.sup.I and z.sup.I axes defining the plate's plane into one or more resonating elements at a non-zero degrees in-plane rotation angle in relation to the plate's x.sup.I axis. The resonator has reduced sensitivity to mechanical acceleration.

A semiconductor device is provided. The semiconductor device incudes: a first sub-semiconductor structure including a dielectric layer; and a second sub-semiconductor structure, at least including a carrier substrate, and being bonded to the first sub-semiconductor structure. The first sub-semiconductor structure or the second sub-semiconductor structure includes a charge accumulation preventing layer, and the charge accumulation preventing layer is disposed between the carrier substrate and the dielectric layer, and is configured to avoid an undesired conductive channel from being generated due to charge accumulation on a surface of the carrier substrate.

A resonator device includes: a base having a first surface and a second surface that are in front-back relation; a resonator element that is located at a first surface with respect to the base and that includes a resonation substrate and an electrode disposed at a surface of the resonation substrate on a base side; a conductive layer that is disposed at the first surface and that includes a joint portion joined to the electrode; and a stress relaxation layer that is interposed between the base and the conductive layer and that at least partially overlaps with the joint portion in a plan view of the base. The stress relaxation layer includes an exposed portion exposed from the conductive layer.

Acoustic resonators are disclosed. An acoustic resonator includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces. The back surface is attached to the surface of the substrate except for a portion of the piezoelectric plate forming a diaphragm spanning a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface of the piezoelectric plate. The IDT includes: a first busbar and a second busbar disposed on respective portions of the piezoelectric plate other than the diaphragm; a first set of elongate fingers extending from the first bus bar onto the diaphragm; and a second set of elongate fingers extending from the second bus bar onto the diaphragm, the second set of elongate fingers interleaved with the first set of elongate fingers.

An acoustic wave device includes a piezoelectric film and an IDT electrode on the piezoelectric film. The IDT electrode includes first and second busbars, at least one first electrode finger, and at least one second electrode finger. When an overlap region is defined as a region in which the first and second electrode fingers overlap each other in an acoustic wave propagation direction, points A2, B2, C2, and D2, defined as follows, are all outside the cavity when, at the points A2, B2, C2, and D2, xa>about 25 μm, ya>about 25 μm, xb>about 25 μm, yb>about 25 μm, xc>about 25 μm, yc>about 25 μm, xd>about 25 μm, and yd>about 25 μm.

A resonator device includes: a base having a first surface and a second surface that are in front-back relation; a resonator element that is located at a first surface with respect to the base and that includes a resonation substrate and an electrode disposed at a surface of the resonation substrate on a base side; a conductive layer that is disposed at the first surface and that includes a joint portion joined to the electrode; and a stress relaxation layer that is interposed between the base and the conductive layer and that at least partially overlaps with the joint portion in a plan view of the base. The stress relaxation layer includes an exposed portion exposed from the conductive layer.

An acoustic wave device including an IDT electrode on a piezoelectric film, in which a Z-axis direction of a crystal is different from a direction of a normal to a major surface. An overlap region of the IDT electrode includes a central region and first and second edge regions. First and second dielectric films are stacked between the piezoelectric film and first and second electrode fingers in the first and second edge regions. When an angle between a first side surface of the first dielectric film and a major surface of the piezoelectric film is α1 and an angle between a second side surface of the second dielectric film and the major surface of the piezoelectric film is α2, α1≠α2 between at least one electrode finger of the first and second electrode fingers and the piezoelectric film.

Aspects of this disclosure relate to methods of manufacturing bulk acoustic wave components. Such methods include plasma dicing to singulate individual bulk acoustic wave components. A buffer layer can be formed over a substrate of bulk acoustic wave components such that streets are exposed. The bulk acoustic wave components can be plasma diced along the exposed streets to thereby singulate the bulk acoustic wave components

A vibration element includes: a quartz crystal substrate having a first vibration part and a second vibration part; a pair of first excitation electrodes formed at two main surfaces of the quartz crystal substrate, at the first vibration part; and a pair of second excitation electrodes formed in such a way as to sandwich the second vibration part in a direction of thickness of the quartz crystal substrate, at the second vibration part. At least one second excitation electrode of the pair of second excitation electrodes is formed at an inclined surface inclined to at least one of the two main surfaces.

A bulk acoustic wave resonator may include: an air cavity; an etching stop layer and an etching stop part, which define a lower boundary surface and a side boundary surface of the air cavity; and a resonating part formed on an approximately planar surface, which is formed by a upper boundary surface of the air cavity and a top surface of the etching stop part. A width of a top surface of the etching stop part may be greater than a width of a bottom surface of the etching stop part. A side surface of the etching stop part connecting the top surface of the etching stop part to the bottom surface of the etching stop part may be inclined.