Tdk Corporation

Tetsuhiro Takahashi

Kenichi Yoshida

Yoshihiko Yano

Daiki Ishii

Yuki Yamashita

Toshihiro Iguchi

Tomohisa Fukuoka

Hiroki Akiba

Ryota Nomura

Tatsuya Ishii

Toshihiko Kaneko

Yasuo Watanabe

Tomoko Suzuki

Masakazu Hosono

Taisuke Masuko

Sanshiro Aman

Saori Takeda

Akinori Ohi

Provided is a dielectric composition containing: a main component expressed by {BaSr}TaO; and a first subcomponent, m satisfying a relationship of 1.95≤m≤2.40. The first subcomponent includes silicon and magnesium. When the amount of the main component contained in the dielectric composition is set to 100 parts by mole, the amount of silicon contained in the dielectric composition is 7.5 to 15.0 parts by mole in terms of SiO, and the amount of magnesium contained in the dielectric composition is 5.0 to 22.5 parts by mole in terms of MgO.

Dielectric composition and electronic component

A thin film capacitor includes: a metal foil having a roughened upper surface; a dielectric film covering the upper surface of the metal foil and having an opening through which the metal foil is partly exposed; a first electrode layer contacting the metal foil through the opening; a second electrode layer contacting the dielectric film without contacting the metal foil; and an insulating member separating the first and second electrode layers. The insulating member has a tapered shape in cross section. With the above configuration, both the first and second electrode layers can be disposed on the upper surface of the metal foil. In addition, since the insulating member has a tapered shape in cross section, adhesion performance of the insulating member can be enhanced, thus making it possible to prevent short-circuit between the first and second electrode layers.

Thin film capacitor, its manufacturing method, and electronic circuit substrate having the thin film capacitor

Provided is a dielectric composition containing: a main component expressed by {BaSr}TaO; and a first subcomponent, m satisfying a relationship of 1.95≤m≤2.40. The first subcomponent includes silicon and manganese. When the amount of the main component contained in the dielectric composition is set to 100 parts by mole, the amount of silicon contained in the dielectric composition is 5.0 to 20.0 parts by mole in terms of SiO, and the amount of manganese contained in the dielectric composition is 1.0 to 4.5 parts by mole in terms of MnO.

To provide a thin film capacitor in which peeling-off of an electrode layer is less likely to occur. A thin film capacitor includes a metal foil having a roughened upper surface, a dielectric film covering the upper surface of the metal foil and having an opening for partly exposing the metal foil therethrough, a first electrode layer contacting the metal foil through the opening and further contacting the dielectric film, and a second electrode layer contacting the dielectric film without contacting the metal foil. With this configuration, both the first and second electrode layers can be disposed on the upper surface of the metal foil. In addition, the first electrode layer contacts not only the metal foil but also the dielectric film, making peeling of the first electrode layer less likely to occur.

Thin film capacitor and electronic circuit substrate having the same

A thin film capacitor includes: a metal foil having a roughened upper surface; a dielectric film covering the upper surface of the metal foil and having an opening through which the metal foil is partly exposed; a first electrode layer contacting the metal foil through the opening; a second electrode layer contacting the dielectric film without contacting the metal foil; and an insulating member provided on the upper surface of the metal foil to surround the first and second electrode layers. The metal foil has an outer peripheral area which is positioned outside an area surrounded by the insulating member and which is not covered with the first and second electrode layers. A height of the electrode layer is equal to or higher than a height of the insulating member. This makes the outer peripheral portion of the thin film capacitor have a step-like shape.

A ceramic electronic device includes an element body including a ceramic layer and an internal electrode layer, and an external electrode formed on an end surface of the element body and electrically connected to at least one end of the internal electrode layer. The external electrode includes a baked electrode layer. The baked electrode layer includes a main component comprising copper and/or a copper alloy. The baked electrode layer includes a void. An inner wall surface defining the void is at least partly covered by a film comprising nickel and/or a nickel alloy.

Ceramic electronic device having a copper-containing baked electrode layer

To provide a thin film capacitor having high adhesion with respect to a circuit substrate. A thin film capacitor includes: a metal foil having a roughened upper surface; a dielectric film covering the upper surface of the metal foil and having an opening through which the metal foil is partly exposed; a first electrode layer contacting the metal foil through the opening; and a second electrode layer contacting the dielectric film without contacting the metal foil. An angle θa formed by the other main surface of the metal foil and a side surface thereof is more than 20° and less than 80°. The side surface is thus tapered at an angle of more than 20° and less than 80°, so that it is possible to suppress warpage and to enhance adhesion with respect to a multilayer substrate when the thin film capacitor is embedded in the multilayer substrate.

To provide a thin film capacitor in which warpage is less likely to occur. A thin film capacitor includes: a metal foil having roughened upper and lower surfaces; a dielectric film covering the upper surface of the metal foil and having an opening through which the metal foil is partly exposed; a dielectric film covering the lower surface of the metal foil and made of a dielectric material having a thermal expansion coefficient smaller than that of the metal foil; a first electrode layer contacting the metal foil through the opening; and a second electrode layer contacting the first dielectric film without contacting the metal foil. The lower surface of the metal foil is thus covered with the dielectric film having a small thermal expansion coefficient, thereby making it possible to prevent the occurrence of warpage.

In order to provide a dielectric composition having high density even when fired at a relatively low temperature, the main component of a dielectric composition includes tantalum and at least one of barium or strontium, and the subcomponent of the dielectric composition includes at least one element selected from the group consisting of vanadium, titanium, and aluminum.

A ceramic electronic device including a ceramic body having ceramic layers and internal electrode layers stacked in alternating manner and a terminal electrode formed at an end face of the ceramic body. The terminal electrode includes a base electrode including a metal component and a glass component, an intermediate electrode layer including Ni and formed at an outer face of the base electrode layer, and an upper electrode layer including Pd or Au and formed at an outer face of the intermediate electrode layer. Also, a surface roughness Ra1 of the base electrode layer in the terminal electrode is 5.0 &#x3bc;m or less; or the surface roughness Ra1 of the base electrode layer, a surface roughness Ra2 of the intermediate electrode layer, and a surface roughness Ra3 of the upper electrode layer satisfy a relationship of Ra1&#x3e;Ra3&#x2265;Ra2.

Ceramic electronic device with varying roughness terminal electrode

To improve a mounting reliability while maintaining a thickness of the external electrode at a side face of a multilayer electronic component thin. The multilayer electronic component includes ceramic body in which ceramic layers and an external electrode formed to an end face of the ceramic body. The upper electrode layer includes an element having higher standard electrode potential than Cu. The external electrode includes an external electrode end part and an external electrode extension part which is integrally formed with the external electrode end part. 1.20&#x2264;t2/t1&#x2264;4.50 is satisfied in which t1 is a total thickness of a thickness of the intermediate electrode layer thickness and t2 is a length from an end of the base electrode layer to an end of the upper electrode layer along the first axis of the external electrode extension part connected by the conductive adhesive.

Multilayer electronic component and mounting structure thereof

A dielectric composition comprising a main component expressed by a chemical formula of (ABCDO, 0&#x2264;x&#x2264;5), wherein said 'A' component is at least one element selected form the group consisting of Ba, Ca, and Sr, said 'B' component is at least one element selected from the group consisting of Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, said &#x201c;C&#x201d; component is at least one element selected from the group consisting of Ti, and Zr, said &#x201c;D&#x201d; component is at least one element selected from the group consisting of Nb, and Ta, and said dielectric composition comprises 2.50 mol or more and 20.00 mol or less of an oxide of Ge as a first sub component with respect to 100 mol of said main component.

Dielectric composition, dielectric element, electronic device, and multilayer electronic device

A dielectric composition is provided. The dielectric composition includes a tungsten bronze type complex oxide expressed by a chemical formula (KNa)SrNbOas a main component, x satisfying 0&#x2264;x&#x2264;0.50, wherein the dielectric composition includes a secondary phase of at least one or more selected from: MgO.SiO; BaO.2MgO.2SiO; and 2MgO.BO; or the dielectric composition includes a tungsten bronze type complex oxide expressed by a chemical formula (KNa)SrNbOas a main component, x satisfying 0&#x2264;x&#x2264;0.40, wherein the dielectric composition includes: MgO; BaO; BO; SiO; and POas a first accessory component in a total content of 2.5 mol to 20.0 mol per 100 mol of the main component.

A dielectric composition is provided. The dielectric composition includes: a main component made of: a first complex oxide expressed by a chemical formula {K(BaSr)NbO}; and a second complex oxide expressed by a chemical formula that differs the chemical formula of the first complex oxide. The second complex oxide is a complex oxide expressed by one of chemical formulae: {(CaSr)(ZrTi)O}; {Ba(TiZr)O}; {(CaSr)TiSiO}; and {(BaRe)NbO}, x satisfies 0.35&#x2264;x&#x2264;0.75, and a satisfies 0.25&#x2264;a&#x2264;0.75 when a molar ratio between the first and second complex oxides is defined by a:b in an order and a+b=1.00.

A dielectric ceramic composition of the invention comprises: BaTiOas a main component, MgO: 0.50 to 3.0 moles, MnO: 0.05 to 0.5 moles, oxide (REO) of element selected from Sm, Eu, and Gd, oxide (REO) of element selected from Tb and Dy, oxide (REO) of element selected from Y, Ho, Er, Yb, Tm and Lu, BaZrO: 0.20 to 1.0 moles, and oxide of element selected from V, Ta, Mo, Nb, and W: 0.05 to 0.25 moles as subcomponents wherein each subcomponent is calculated as a conversion of an oxide or composite oxide, with respect to 100 moles of the main component, and contents of said REO, REOand REOsatisfy REO&#x3c;REOand (REO+REO)&#x2266;REO.

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Tokyo, Japan

Tetsuhiro Takahashi