Ngk Insulators, Inc.

Ngk Ceramic Device Co., Ltd.

Ngk Ceramic Device Ltd.

Takashi Ebigase

Hideki Shimizu

Makoto Tani

Yoshihiro Tanaka

Takeshi Kaku

Takao Ohnishi

Toshikatsu Kashiwaya

Shingo Iwasaki

Tomohiko Hibino

Izumi Masuda

Shinya Takemura

Takaaki Koizumi

Naoki Goto

Yasutaka Awakura

Shinji Shiranita

Koji Katsu

Kenichi Tsuge

A bonded substrate includes a ceramic substrate, a copper plate, and a bonding layer. The ceramic substrate has a main surface having a flat region having a maximum height Rz of 10 μm or less. The ceramic substrate has a particle-defect hole being exposed to the main surface, imparting flatness lower than flatness of the flat region to a part of the main surface, and having a depth of 10 μm or more and 60 μm or less. The copper plate includes a first portion disposed over the flat region and a second portion filling the particle-defect hole. The bonding layer includes a third portion covering the flat region and a fourth portion filling the particle-defect hole, and the second portion and the fourth portion fill 80% or more of a volume of the particle-defect hole. The bonding layer bonds the copper plate to the main surface.

Bonded substrate, and bonded substrate manufacturing method

The bonded substrate includes the silicon nitride ceramic substrate, a copper plate, the bonding layer, and penetrating regions. The copper plate and the bonding layer are patterned into a predetermined shape, and are disposed over a main surface of the silicon nitride ceramic substrate. The bonding layer bonds the copper plate to the main surface of the silicon nitride ceramic substrate. The penetrating regions each include one or more penetrating portions penetrating continuously from the main surface of the substrate into the silicon nitride ceramic substrate to a depth of 3 μm or more and 20 μm or less, and contain silver, and the number of penetrating regions present per square millimeter of the main surface of the substrate is one or more and 30 or less.

Bonded substrate and bonded substrate manufacturing method

A bonded substrate includes: a silicon nitride ceramic substrate; a copper plate; and a bonding layer bonding the copper plate to the silicon nitride ceramic substrate, wherein the bonding layer has a first interface in contact with the silicon nitride ceramic substrate and a second interface in contact with the copper plate, and contains a nitride and a silicide of an active metal as at least one metal selected from the group consisting of titanium and zirconium, an atomic fraction of nitrogen of the bonding layer is greatest at the first interface and is smallest at the second interface, and a sum of atomic fractions of the active metal and silicon of the bonding layer is smallest at the first interface and is greatest at the second interface.

Bonded substrate, and method for manufacturing bonded substrate

A second main surface of the copper plate is opposite a first main surface of the copper plate, and is bonded to a silicon nitride ceramic substrate by the bonding layer. A first portion and a second portion of an end surface of the copper plate form an angle of 135° to 165° on an outside of the copper plate. An extended plane of the first portion and the second main surface form an angle of 110° to 145° a side where the second portion is located. A distance from the second main surface to an intersection of the first portion and the second portion in a direction of a thickness of the copper plate is 10 to 100 μm. The second main surface extends beyond the extended plane of the first portion by a distance of 10 μm or more.

Bonded substrate and manufacturing method of bonded substrate

An insulated heat dissipation substrate including: a ceramic substrate; and a conductor layer bonded onto at least one of main surfaces of the ceramic substrate, wherein the conductor layer includes: an upper surface; a lower surface; and a side surfaceconnecting the upper surface with the lower surface; the ceramic substrate includes: a lowest portion; a side surfaceconnecting the lowest portion with the side surfaceof the conductor layer; and a bonding surface at a position higher than the lowest portion, the bonding surface being bonded to the lower surface of the conductor layer; an absolute value (|&#x3b1;&#x2212;&#x3b2;|) is 20&#xb0; or less on average; and the side surfacehas a receding portion from an end of the upper surface in the normal direction relative to the tangential line of the contour of the conductor layer as viewed in plane.

Insulated heat dissipation substrate

An insulated heat dissipation substrate including: a ceramic substrate; and a conductor layer bonded onto at least one of main surfaces of the ceramic substrate, wherein the conductor layer includes an upper surface, a lower surface bonded to the ceramic substrate, and a side surface connecting the upper surface with the lower surface wherein, a tip of the upper surface recedes in the normal direction of the conductor layer from a tip of the lower surface, the side surface has a contour having an inwardly recessed curve line and having a portion receding in the normal direction of the conductor layer from the tip of the upper surface, and a connection portion between the upper surface and the side surface has a rounded shape such that a maximum radius R of a circle is 0.1 &#x3bc;m&#x2264;R&#x2264;5 &#x3bc;m on average.

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 piezoelectric/electrostrictive ('PE') actuator includes a PE element including a laminated object having a PE layer and a pair of electrodes arranged respectively on both sides of the PE layer, and having an operating part corresponding to the portion in which the PE layer is sandwiched between the pair of electrodes and a non-operating part corresponding to the portion in which the PE layer is not sandwiched between the pair of electrodes, and a moisture-proof film covering at least the vicinity of a boundary between the operating part and the non-operating part, consisting of a liquid with a saturated moisture content at 25 degree Celsius of 300 ppm or less and a withstand voltage at the saturated moisture content of not less than 6 kV/mm. The liquid contains hydrocarbon system organic compound having a main backbone of carbon-carbon bond and consisting only of carbon and hydrogen.

Piezoelectric/electrostrictive actuator

A piezoelectric/electrostrictive element having a piezoelectric body, a through-hole electrode, a first electrode, a second electrode, a third electrode. The piezoelectric body includes a through-hole in communication with a first main surface and a second main surface. The through-hole electrode is formed on an inner side surface of the through-hole. The first electrode is formed on the first main surface of the piezoelectric body, and connected to the through-hole electrode. The second electrode is formed on the second main surface of the piezoelectric body, and is connected to the through-hole electrode. The third electrode is formed on the second main surface of the piezoelectric body and isolated from the second electrode. A calculated average roughness in the inner side surface is larger than 0.11 microns and smaller than 16 microns. A maximum height roughness in the inner side surface is larger than 0.2 microns and smaller than 20 microns.

Piezoelectric/electrostrictive element and method for manufacturing the same

Provided is a piezoelectric/electrostrictive film type element in which the film thickness of the piezoelectric/electrostrictive film is small, the piezoelectric/electrostrictive film is dense, and the piezoelectric/electrostrictive film has good durability and insulation quality. The piezoelectric/electrostrictive film type element includes a substrate, a lower electrode film, a piezoelectric/electrostrictive film and an upper electrode film. The substrate and the lower electrode film are fixed adherently each other. The film thickness of the piezoelectric/electrostrictive film is 5 &#x3bc;m or less. The piezoelectric/electrostrictive film is composed of a piezoelectric/electrostrictive ceramic. The piezoelectric/electrostrictive ceramic contains lead zirconate titanate and a bismuth compound. The bismuth/lead ratio in the peripheral section inside the grain which is relatively close to the grain boundary is greater than the bismuth/lead ratio in the center section inside the grain which is relatively far from the grain boundary.

Piezoelectric/electrostrictive film type element containing lead zirconate titanate and a bismuth compound and method for producing the same

A piezoelectric/electrostrictive element has a piezoelectric body, a first electrode, a second electrode and a glass layer. The piezoelectric body is formed in a thin film-shape. The piezoelectric body has a first main surface and a second main surface. The first electrode is disposed on the first main surface of the piezoelectric body. The first electrode has an electrode side surface configured to be connected with the first main surface. The second electrode is disposed on the second main surface of the piezoelectric body. The glass layer is continuously formed on the first main surface and the electrode side surface. The glass layer containing glass as a principal constituent. The glass layer is isolated from the side surface of the piezoelectric body.

Piezoelectric/electrostrictive element

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 method of manufacturing a piezoelectric element including a step of preparing a green sheet A including a portion which becomes a fired piezoelectric body later, by use of a piezoelectric material; a step of joining, to at least one surface of the green sheet A, a green sheet B having an opening in a portion facing the portion which becomes the fired piezoelectric body later, followed by firing to obtain the fired piezoelectric body provided with a reinforcing plate to which the reinforcing plate formed owing to the firing of the green sheet B is attached; and a step of forming a film-like electrode in a portion obtained by the firing of the green sheet A in the fired piezoelectric body provided with the reinforcing plate.

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Nagoya, Japan

Takashi Ebigase