Ngk Insulators, Inc.

Makoto Tani

Shinsuke Yano

Takashi Ebigase

Hideki Shimizu

Yoshihiko Ishida

Yoshihiro Tanaka

Takami Hirai

Shoji Seike

Masayuki Uetani

Hirokazu Nakanishi

Tsutomu Nanataki

Takayuki Kikuchi

Takao Ohnishi

Shigeki Hayashi

Yuji Asai

Tomohiro Yamada

Seiji Ishikawa

Takeshi Kaku

Kazuyuki Matsuda

Daishi Tanabe

Yasutaka Awakura

Takashi Wada

Tooru Hayase

Provided is a bonded substrate mainly for mounting a power semiconductor in which the reliability to a thermal cycle has been enhanced as compared with a conventional one. In a bonded substrate in which a copper plate is bonded to one or both main surface(s) of a nitride ceramic substrate, a bonding layer consisting of TiN intervenes between the nitride ceramic substrate and the copper plate and is adjacent at least to the copper plate, and an Ag distribution region in which Ag atoms are distributed is set to be present in the copper plate. Preferably, an Ag-rich phase is set to be present discretely at an interface between the bonding layer and the copper plate.

Bonded substrate and method for manufacturing bonded substrate

A ceramic circuit board includes a ceramic substrate, a first metal plate bonded to a front surface of the ceramic substrate, and a member bonded to a front surface side of the metal plate. The member is made up from a material which exhibits a lower coefficient of thermal expansion than that of the first metal plate, and which exhibits a higher Young's modulus than that of the first metal plate.

Ceramic circuit board and electronic device

A heat dissipating circuit board for a power semiconductor includes an electrode material on which a power semiconductor is mounted on a front surface thereof, and a member bonded to a front surface side of the electrode material. The member is made up from a material which exhibits a lower coefficient of thermal expansion than that of the electrode material, and which exhibits a higher Young's modulus than that of the electrode material.

Heat dissipating circuit board and electronic device

A ceramic circuit board includes a ceramic substrate, and a first metal plate bonded to a front surface of the ceramic substrate. A size of the front surface of the ceramic substrate is smaller than a size of a surface, i.e., a first facing surface, on a side of the first metal plate that faces the ceramic substrate.

A substrate for a light-emitting diode comprising a metal base with a thickness of a predetermined value or more is constituted so that the thickness of a top conductor for an electrical connection with a light-emitting diode (LED) in a predetermined range falls within a predetermined range and the thickness of an insulation layer which electrically insulates the metal base and the top conductor and the thickness of the top conductor meet a predetermined relation. Thereby, a substrate for a light-emitting diode which can show a high heat dissipation capacity by achieving a low thermal resistance as the total thermal resistance of the whole substrate without reducing insulation reliability and high-humidity reliability of the substrate is provided.

Substrate for light-emitting diode

A substrate for a light-emitting diode comprising a metal base with a thickness of a predetermined value or more is constituted so that the thickness of a top conductor for an electrical connection with a light-emitting diode (LED) in a predetermined range falls within a predetermined range and the thickness of an insulation layer which electrically insulates the metal base and the top conductor and the thickness of the top conductor meet a predetermined relation. Thereby, a substrate for a light-emitting diode which can show a high heat dissipation capacity by achieving a low thermal resistance as the total thermal resistance of the whole substrate without reducing an insulation reliability and high-humidity reliability of the substrate is provided.

An aspect of a piezoelectric actuator according to the present invention comprises: a plate-like piezoelectric element (); a sheet (); and a movable body (). The piezoelectric element is provided to the sheet () in such a manner that the upper surface of the plate-like piezoelectric element is parallel to the upper surface of the sheet. The sheet includes a movable body driving section () formed on one of the upper and the lower surfaces of the sheet. A movable body includes a contact section () contacting with the sheet at the movable body driving section. The actuator moves the movable body driving section in a direction parallel to the upper surface of the sheet by using expansion and contraction of the piezoelectric element in a direction parallel to the upper surface of the piezoelectric element to move the movable body.

Piezoelectric actuator and piezoelectric actuator array

A piezoelectric actuatoraccording to each embodiment of the present invention comprises: a column-like piezoelectric body, whose bottom face is fixed to a base portion, and which stands from the base portion; and a driving power supply section for applying a driving voltage to the piezoelectric body. The piezoelectric body includes two sets () of a pair of electrodes for providing electrical fields to the piezoelectric body. The two sets are formed so that each of the two sets is provided to each of two regions into which the piezoelectric body is divided by a virtual plane VPLparallel to the center axis CL of the piezoelectric body. The driving power supply section applies the driving voltage Vin having a 'frequency between the second-order bending resonant frequency and the first-order expansion-contraction resonant frequency' to either one of the two sets, selectively.

An electronic device includes a layered piezoelectric element and a driven member. The driven member is bonded to the top surface of the layered piezoelectric element by means of an epoxy resin adhesive. The piezoelectric element includes a side electrode on one side surface of the element, which is one of the outer surfaces of the element. The piezoelectric element includes, in the vicinity of the upper end portion of the side surface, a dam portion formed of a material for preventing epoxy bleed out of the adhesive. Therefore, even when the epoxy bleed out of the adhesive occurs, a bled-out portion of the components of the adhesive does not reach the side electrode. Thus, when the side electrode is connected to an external circuit by, for example, soldering, reduction in the connection strength or similar problems are avoided.

Electronic device

A device using a piezoelectric element includes a layered piezoelectric element and a driven member. The layered piezoelectric element includes an active portion formed of stacked piezoelectric layers each being sandwiched between a first internal electrode layer and a second internal electrode layer, and an inactive portion (first end inactive portion) formed of a first end piezoelectric layer stacked on the active portion. The driven member is bonded to the top surface of the first end piezoelectric layer by means of an adhesive. The piezoelectric layers and the first end piezoelectric layer are formed such that the porosity of the inactive portion is greater than that of the active portion. Therefore, since numerous open pores are emerged on the top surface of the first end piezoelectric layer, the adhesive enters into the open pores to have the driven member be strongly bonded to the top surface.

Device utilizing piezoelectric element

A circuit board that can decrease thermal stress acting between a semiconductor element and a board in association with temperature alteration and has high mechanical strength (rigidity) as a whole board (including a multilayer wiring layer) is provided. Ceramic base material having a coefficient of thermal expansion close to that of a semiconductor element and inner layer wiring are integrally sintered, and the circuit board is configured so that fine-lined conductor structure corresponding to a multilayer wiring layer in the inner layer wiring has predetermined width, intralayer interval and interlayer interval. Thereby, thermal stress acting between a semiconductor element and the board when the board is exposed to temperature alteration in a condition where it is joined with the semiconductor element is suppressed, rigidity of the board is maintained, and its reliability against temperature cycle is increased.

Laminated and sintered ceramic circuit board, and semiconductor package including the circuit board

In the laminated and sintered ceramic circuit board according to the present invention, at least a portion of the inplane conductor is fine-lined, such that the shape of the cross-section surface of the fine-lined inplane conductor is trapezoid, and the height (a), the length (c) of the lower base and the length (d) of the upper base of the trapezoidal cross-section surfaces, and the interval (b) between the lower bases of the trapezoidal cross-section surfaces of the inplane conductors adjacent in a plane parallel to the principal surfaces of the board meet a certain relation. This provides a laminated ceramic circuit board with low open failure rate, short-circuit failure rate and high reliability against high temperature and high humidity in a downsized and short-in-height (thin) semiconductor package.

A method for manufacturing a piezoelectric/electrostrictive element includes a step of subjecting the piezoelectric/electrostrictive film to a heat treatment and a polarization treatment after the film is allowed to stand until the value of an electric constant has converged after the heat treatment. The piezoelectric/electrostrictive element manufactured in this method has small stress remaining in the piezoelectric/electrostrictive film, and predetermined performance regarding, for example, a displacement amount, a displacement-generating force, and an electric power efficiency (consumed electric power) as a piezoelectric/electrostrictive element (piezoelectric/electrostrictive film) is never spoiled.

Piezoelectric/electrostriction element manufacturing method

An object of the present invention is to provide a novel structure of supporting a vibrator having a terminal for electrical connection so that the vibrator can be miniaturized, and the driving impedance can be made constant in a wide temperature range to reduce the temperature drift. The structure has a substrate and bonding wiressupported on the surface of the substrate and to be connected with the vibrator. The vibrator is supported with the bonding wire so that the vibrator is not directly contacted with the substrate. The bonding wire is electrically connected with the terminal. The resonance frequency 'fr' of the supporting structure, the driving frequency 'fd' for the vibrator and the detuning &#x201c;&#x394;f&#x201d; satisfy the following formula1.1&#x2266;0.9

Structures for supporting vibrators

The invention reduces the noise from a vibrating gyroscope used for detecting a turning angular rate, when the vibrator is subjected to external vibration. The vibrator is made out of a piezoelectric material. The vibrator vibrates in a driving vibration mode electrically excited in the vibrator and in a detection vibration mode occurring in the vibrator due to Coriolis force when the vibrator is turned. The surface of the vibrator includes a region where the stress induced in the vibrator due to the detection vibration mode is in a range of a local maximum. The gyroscope further has a damper, for reducing vibration sensitivity to external vibrations applied externally on the vibrator. The damper is made of a polymer and is provided on at least the region where the stress induced in the vibrator due to the detection vibration mode is in a range of a local maximum.

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Inazawa, Japan

Makoto Tani