Nihon Dempa Kogyo Co., Ltd.

Takefumi Saito

Mitoshi Umeki

Ryoichi Ichikawa

Yoshiaki Amano

Takahiro Inoue

Noritoshi Kimura

A vibrator includes a base substrate, a tuning fork type vibrating body, a first vibrating body, a second vibrating body, a first extraction electrode at the one vibration arm portion, a second extraction electrode at the other vibration arm portion, and an input/output port at the base portion. The input/output port is configured to input/output an electric signal to/from each of the first extraction electrode, the second extraction electrode, and the excitation electrodes of the vibration arm portions. The tuning fork type vibrating body is configured to generate a flexural vibration in reverse phase to the contour vibration of the first and second vibrating bodies, so as to absorb the contour vibration of the first and second vibrating bodies.

Tuning fork configured to generate flexural vibration in reverse phase to the contour vibration of first and second vibrating bodies

Surface-mounted piezoelectric devices are disclosed, of which an exemplary device includes a tuning-fork type piezoelectric vibrating piece having a base portion and a pair of vibrating arms extending from the base portion. The device includes a package defined by a wall. The package includes a cavity accommodating the tuning-fork type piezoelectric vibrating piece and at least one columnar body situated between the vibrating arms in the cavity.

Stiffness-enhanced surface-mounted piezoelectric devices

An exemplary piezoelectric vibrating device includes a piezoelectric frame that supports and surrounds a tuning-fork type piezoelectric vibrating piece having a pair of vibrating arms. The device also includes a lid and a package base that are siloxane-bonded to the frame. The lid defines at least one frequency-adjustment hole extending through the thickness dimension of the lid from an inner major surface thereof (facing the frame) to an outer major surface of the lid. The package base defines at least one through-hole electrode passing via a respective electrode through-hole through the thickness of the base from an inner major surface thereof (facing the frame) to the outer major surface thereof. The electrode is connected to the piezoelectric vibrating piece. The lid and base include external electrodes, made of an electrically conductive material, that cover the through-holes and frequency-adjustment hole(s).

Piezoelectric devices and methods for manufacturing same

A tuning-fork type crystal vibrating piece () is comprised of a base portion () comprising a piezoelectric material, a pair of parallel vibrating arms () with a designated thickness (D) and width (W) extend from the base portion, and a pair of weight portions () are formed by enlarging the width (W) of the distal ends pair of vibrating arms. A cross-section of the pair of weight portions is formed symmetric with a central axis which is center of the pair of vibrating arms, and at least one portion of the pair of weight portions has a thickness which is less than the designated thickness (D).

Tuning-fork type piezoelectric vibrating piece, piezoelectric frame, piezoelectric device, and a manufacturing method of tuning-fork type piezoelectric vibrating piece and piezoelectric frame

Methods are disclosed for manufacturing piezoelectric vibrating pieces and devices including such pieces. According to an embodiment of the method, a piezoelectric vibrating piece is produced from a piezoelectric wafer. To form the piece, a profile of the piezoelectric vibrating piece is formed in a piezoelectric wafer. A first metal film (chromium; Cr) is formed on the surface of the piezoelectric piece. The chromium film is surface-oxidized to form a film having Cr foundation layer and an oxidized surface. A second metal film (gold; Au) is formed on the oxidized surface. Then, in selected regions not destined to become electrodes, the second metal film is removed, leaving electrode patterns at designated regions of the piezoelectric vibrating piece.

Surface-mounted piezoelectric devices are disclosed that include a package having a base and a lid made of a piezoelectric material or of glass. The package defines an internal cavity containing a tuning-fork type crystal vibrating piece having a pair of vibrating arms. The volume of the cavity is at least twelve times the volume of the pair of vibrating arms. Piezoelectric devices having these characteristics exhibit reduced CI degradation.

Piezoelectric devices exhibiting reduced CI degradation

When forming an opening conforming to a groove of a quartz resonator in a metal film serving as a mask of the quartz resonator by conducting etching, the outer periphery of the metal film is wavingly etched. Therefore, when the groove is formed on the quartz resonator, the quartz resonator is formed according to the above-described metal film, which results in appearance defects or dimension defects. In order to solve the problems, the outer shape of the metal film is formed smaller than the outer shape of the quartz resonator before forming the opening conforming to the groove of the quartz resonator in the metal film, then etching of the metal film and etching of the quartz resonator are performed.

Method of manufacturing piezoelectric resonator

Crystal devices are disclosed that include a crystal frame having a crystal vibrating piece and an outer frame. The crystal vibrating piece includes excitation electrodes, and the outer frame supports the crystal vibrating piece. Each device has a base including connection electrodes on a first surface thereof and respective external electrodes on a second surface thereof, wherein the connection electrodes are electrically connected via respective through-holes to respective excitation electrodes and to respective external electrodes. The first surface of the base is bonded to the under-surface of the outer frame, and an upper surface of the outer frame is bonded to a crystal lid. The through-holes have non-circular transverse profiles and are filled with a sealing material such as a metal.

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Saitama, Japan

Takefumi Saito