A piezoelectric vibration component that includes a substrate having a principal surface and a side face, a piezoelectric vibrator, a lid, and an adhesive layer that hermetically seals the piezoelectric vibrator in a space between the lid and the principal surface. The adhesive layer extends from the principal surface to at least a portion of the side face of the substrate.

A quartz crystal resonator unit that includes a quartz crystal resonator, a lid member and a base member defining an internal space that accommodates the quartz crystal resonator, and a sealing frame and a joining material joining the lid member and the base member to each other. In a plan view of a principal surface of the base member, the sealing frame and the joining material have a frame shape surrounding the quartz crystal resonator, and the frame shape has a uniform width.

A piezoelectric oscillation device includes a piezoelectric vibration element, a heating element that heats the piezoelectric vibration element, an electronic component that is electrically connected to the piezoelectric vibration element, a substrate on which the piezoelectric vibrator, the heating element, and the electronic component are mounted, and a base member to which the substrate is attached with a prescribed spacing therebetween via a substrate holding member. The substrate holding member includes a conductive part. The conductive part has a lower thermal conductivity than metal.

An electronic component includes a metal cap including a first main-surface having a flat plate-like shape with a first main surface and an annular portion that has an annular shape and that surrounds the first main surface when viewed in a direction perpendicular to the first main surface. The first main-surface and the annular portion forming a recess. A substrate is provided having a flat plate-like shape with a second main surface that hermetically seals the recess, a joining member that joins the cap and the substrate to each other, with an element accommodated in the recess. An outer peripheral surface of the annular portion has a band-shaped region between the first and second main surfaces in the direction perpendicular to the first main surface. A groove is formed in the band-shaped region that extends in a circumferential direction of the annular portion.

A method for manufacturing a piezoelectric vibration element that includes preparing a piezoelectric substrate; providing a first electrode layer on a first main surface of the piezoelectric substrate; arranging a mask on a side of the first main surface of the piezoelectric substrate, the mask including a center region and a peripheral region located along a periphery of the center region; and irradiating a radiation beam through the mask toward the first main surface of the piezoelectric substrate such that a larger amount of the radiation beam passes through the peripheral region than the center region of the mask so as to remove a part of the first electrode layer to form a first excitation electrode that decreases in thickness from the center region to the peripheral region of the mask on the first main surface of the piezoelectric substrate.

A piezoelectric device is provided and includes: a piezoelectric vibrating piece, having an outer shape in rectangular shape and including an excitation electrode formed on both principal surfaces which are a top surface and a lower surface, an electrode pad formed at both ends of one short side, and an extraction electrode extracted from the excitation electrode to the electrode pad to be electrically connected to the electrode pad; a package, including a placement surface on which the piezoelectric vibrating piece is placed as opposed to the lower surface of the piezoelectric vibrating piece, and an adhesion pad formed on the placement surface; and a conductive adhesive, securing the piezoelectric vibrating piece to the package and electrically connecting the adhesion pad to the electrode pad. An adhesive is applied on the top surface of the piezoelectric vibrating piece and between the conductive adhesive and the excitation electrode.

An AT-cut crystal element is provided. The AT-cut crystal element includes side surfaces intersecting with a Z-axis of a crystallographic axis of a crystal. At least one side surface of the side surfaces is constituted of three surfaces of a first surface to a third surface. Besides, a crystal resonator including the AT-cut crystal element, and a crystal unit including the crystal resonator are provided.

An AT-cut crystal element is provided for reducing unnecessary vibration and for improving impedance of a resonator. Two side surfaces intersecting with a Z-axis of a crystallographic axis of crystal are constituted of three surfaces of a first surface as an m-surface of quartz crystal, a second surface that intersects with the first surface and is other than the m-surface, and a third surface that intersects with the second surface and is other than the m-surface. Moreover, the second surface is a surface corresponding to a surface obtained by rotating a principal surface of the AT-cut crystal element by 743 having an X-axis of crystal as a rotation axis, and the third surface is a surface corresponding to a surface obtained by rotating the principal surface by 563 having the X-axis of the crystal as the rotation axis.

A method for producing an elastic wave device includes steps of (a) preparing a first substrate and a second substrate, (b) irradiating a bonding surface of the first substrate and a bonding surface of the second substrate with one of plasma, neutral atom beams, and ion beams of an inert gas, (c) bonding the bonding surface of the first substrate and the bonding surface of the second substrate in a vacuum at room temperature so as to set a strength that allows the first and second substrates to be separated by insertion of a blade; (d) forming a composite substrate by bonding a piezoelectric substrate to another surface of the first substrate; (e) forming electrode on a surface of the piezoelectric substrate of the composite substrate; and then (f) removing the second substrate from the first substrate by separation with the blade.

A carbon nanotube (CNT) resonator includes: a first CNT having a first end and a second end both fixed to a substrate; and a second CNT having a first end fixed to the substrate. The second CNT creates a Van der Waals (VdW) bond with the first CNT where the second CNT overlaps the first CNT. A length of the VdW bond along a distance between the first and the second CNTs oscillates based on a DC voltage applied between the first end of the first CNT and the first end of the second CNT. An electrical current passing through the first and the second CNTs using the VdW bond oscillates based on the oscillation of the length of the VdW bond.