Tdk Corporation

Kenichi Tochi

Ken Unno

Takao Noguchi

Masahiro Miyazaki

Hiroshi Yamazaki

Tatsuo Namikawa

Shigeru Shoji

Kazuya Maekawa

Hirofumi Sasaki

Akihiro Unno

Takashi Aoyagi

Hirofumi Natori

In a piezoelectric element, a piezoelectric film, a first electrode film provided on one surface of the piezoelectric film, and a second electrode film provided on the other surface of the piezoelectric film form a layered structure, an outer contour of the first electrode film and an outer contour of the second electrode film are positioned outside an outer contour of the piezoelectric film as viewed in a layering direction, an organic resin film is in contact with the piezoelectric film, and generation of noise is suppressed.

Angular velocity sensor

The present invention provides an electronic device with improved characteristics and a method of making the electronic device. In a method of making an electronic device (piezoelectric device)according to the present invention, an outer edge Rof a piezoelectric filmA formed on an electrode filmA of a laminateis located inside an outer edge Rof the electrode filmA. For this reason, in removal of a monocrystalline Si substratefrom a multilayer board, where an etching solution permeates between polyimideand laminate, the etching solution circumvents the electrode filmA before it reaches the piezoelectric filmA. Namely, a route A of the etching solution to the piezoelectric filmA is significantly extended by the electrode filmA. In the method of making the electronic device, therefore, the etching solution is less likely to reach the piezoelectric filmA. It significantly suppresses a situation of dissolution of the piezoelectric filmA and realizes improvement in characteristics of the piezoelectric devicemade.

Electronic device and method of making same

An angular velocity sensor element is provided which is capable of preventing even transmission of sudden externally-applied vibration to an element portion by absorbing the vibration. An angular velocity sensor elementaccording to the present embodiment has a fixing portionin the form of a frame, an element portiondisposed in the frame of the fixing portionand having vibrating armstoin a drive system and a detection system, and a connecting portionformed as a fixed-fixed beam having its both ends connected to the fixing portionand having its intermediate portion connected to the element portion

Angular velocity sensor element

A piezoelectric element having a crystal structure that enables a piezoelectric film to be formed in an unstressed state is provided. The piezoelectric film contains an a-axis oriented crystal and a c-axis oriented crystal, where a difference in lattice constant between the a-axis oriented crystal and the c-axis oriented crystal is not more than 0.06 &#x212b;. The present inventors have newly found that a stress accumulated in the piezoelectric film can be reduced while maintaining favorable piezoelectric properties when a condition that the difference in lattice constant between the a-axis oriented crystal and the c-axis oriented crystal is not more than 0.06 &#x212b; is satisfied. When the condition is satisfied, the c-axis oriented crystal and the a-axis oriented crystal are properly balanced and as a result crystal particles of the piezoelectric film are closest-packed on its base in an ideal state, which contributes to a reduced stress.

Piezoelectric element and gyroscope

An angular velocity sensing element is provided, which is able to prevent breakage of an oscillation arm even when an excessively large shock is given. An angular velocity sensing elementaccording to the present embodiment includes oscillation armsandformed of a semiconductor material, and a stopper member provided to limit the oscillation range of the oscillation arms. As such a stopper member, a first stopper memberis provided, for example, which limits the oscillation range of the oscillation arms at least within a single plane of the arms. Fixing portions, the oscillation armsandand the first stopper memberare integrally formed by processing a semiconductor material, such as silicon.

Angular velocity sensing element

An angular velocity sensor of a horizontally located type, in which influence of a translational acceleration applied thereto from a lateral direction is readily removed and a fixed portion thereof is easily fixed, is provided. It includes a fixed portion fixed to the top surface of a sensor element supporting portion of a casing, an upper detection arm portion and a lower detection arm portion respectively connected to the fixed portion on sides opposite to each other and extending along a plane parallel to the top surface of the sensor element supporting portion, and a pair of upper vibration arms connected to the fixed portion with the upper detection arm portion in between. The fixed portion includes one or more slits extending at least in a direction intersecting with the extending direction of the upper detection arm portion.

Angular velocity sensor and angular velocity sensing device

An angular velocity sensor of a horizontally located type, which can easily remove the translational acceleration influence thereto from the lateral direction, is provided. It includes a fixed portion fixed to the surface of a sensor element supporting portion of a casing, an upper detection arm and a lower detection arm, each of them being connected to the fixed portion on sides opposite to each other and extending along a plane parallel to the surface place of the sensor element supporting portion, and a pair of upper vibration arms connected to the fixed portion in such a manner as to form a pair of arms with the upper detection arm in between and extending in a direction parallel to the extending direction of the upper detection arm.

Proposed is a horizontally located angular velocity sensor hardly affected by a translational acceleration in a lateral direction, and in which a fixed section is easily fixed. The angular velocity sensor includes a fixed section fixed on a support surface. On both sides of the fixed section, an arm section of an upper detection arm and a pair of upper drive arms extending along a plane parallel to the support surface, and an arm section of a lower detection arm and a pair of lower drive arms extending along the plane parallel to the support surface are coupled, respectively. The upper detection arm and the pair of upper drive arms are coupled without the fixed section in between, and the lower detection arm and the pair of lower drive arms are coupled without the fixed section in between.

Angular velocity sensor and angular velocity sensor device

Provided is a horizontally located sensitive angular velocity sensor capable of easily eliminating influence of acceleration in a lateral direction and whose fixed section is easily fixed. The angular velocity sensor includes a pair of fixed sections fixed on a top of an sensor support section of a case, a detection arm extending along a plane parallel to the sensor support section, and a pair of upper drive arm and lower drive arm extending along the plane parallel to the sensor support section and extending in a direction opposite to each other so as to intersect an extending direction of the detection arm.

The present invention provides an angular velocity sensor in which higher sensitivity for sensors is available even with a smaller base portion. The angular velocity sensor includes a fixed portion fixed to the top surface of a sensor element supporting portion of a casing, an upper detection arm and a lower detection arm, each of them being connected to the fixed portion on sides opposite to each other and extending along a plane parallel to the top surface of the sensor element supporting portion, and a pair of upper vibration arms connected to the fixed portion in such a manner as to form a pair of arms with the upper detection arm in between and extending in a direction parallel to the extending direction of the upper detection arm.

Method of making a piezoelectric device

The invention relates to a piezoelectric thin film vibrator having a piezoelectric device formed by using thin film formation technology, a fabrication method thereof, a driving apparatus and a piezoelectric motor using the same, and an object is to provide a piezoelectric thin film vibrator which can provide an excellent piezoelectric characteristic at low cost, a fabrication method thereof, a driving apparatus and a piezoelectric motor using the same. A piezoelectric thin film vibrator is configured to have a resonator which generates a flexure traveling wave, a lower electrode which is formed on the resonator, a piezoelectric thin film which is formed by epitaxial growth on the lower electrode, and a plurality of upper electrode parts which is formed on the piezoelectric thin film.

Piezoelectric thin film vibrator and fabrication method thereof, driving apparatus and piezoelectric motor using the same

A head slider having a thin film magnetic head is mounted on a suspension assembly. The suspension assembly is comprised of a metal plate-like member, and a piezoelectric actuator for displacing the head slider relative to the suspension assembly. The piezoelectric actuator has a piezoelectric film, and a pair of electrode films placed so as to sandwich the piezoelectric film in between. The piezoelectric film and the pair of electrode films are formed in an order of one electrode film, the piezoelectric film, and the other electrode film on the plate-like member.

Suspension assembly, hard disk drive, and method of manufacturing suspension assembly

Provided is a thin-film piezoelectric element which reduces the influence of an oxide film left on the electrode film on the degradation of element characteristics, and a method of making the thin-film piezoelectric element. The thin-film piezoelectric element has ZrOas the main component of the outermost layer of the oxide film which covers the laminate. Young's modulus of the ZrOis 190 GPa, giving a significantly low value compared with Young's modulus of MgO, 245 GPa. Consequently, the influence of the oxide film on the reduction in the displacement magnitude of the piezoelectric film is smaller than the influence of the MgO thin film left in the conventional thin-film piezoelectric element. As a result, the thin-film piezoelectric element decreases the influence of the oxide film on the degradation of element characteristics compared with the conventional thin-film piezoelectric element.

Thin-film piezoelectric element and method of making same

A thin film piezoelectric element has a laminate including a piezoelectric film and a pair of electrode films placed so as to sandwich the piezoelectric film in between, a resin film formed so as to cover the laminate, and an electrode formed on the resin film and electrically connected to the electrode film. The resin film is formed so that a thickness of a region where the electrode is formed is larger than a thickness of a region corresponding to a displaced portion of the laminate.

Growing community of inventors

Tokyo, Japan

Kenichi Tochi