Kyocera Corporation

Takeshi Kubota

Kunihide Shikata

Masahiko Higashi

Noriaki Hamada

Yasuhide Tami

Hideto Yonekura

Kouichi Yamaguchi

Yasuyoshi Kunimatsu

Akifumi Sata

Akira Furuzawa

Akira Furusawa

Yohji Furukubo

In a circuit board obtained by providing a metallized layer of wiring on the surface or interior of an insulation substrate, the insulation substrate is, for example, a multi-layer circuit board or a package for semiconductor element, the insutating substrate obtained from a sintered body having a linear expansion coefficient of 8 to 18 ppm/.degree. C. at 40.degree. to 400.degree. C. which is prepared by sintering a molded body containing 20 to 80% of a glass having a liner expansion coefficient of 6 to 18 ppm/.degree. C. at 40.degree. to 400.degree. C. and 80 to 20% of a filler having a linear expansion coefficient of at least 6 ppm/.degree. C. When the circuit board of the present invention is surface mounted on an outer electric circuit substrate such as a printed wiring board having a large linear expansion coefficient, the occurrence of stress due to a difference between the linear expansion coefficients of both is suppressed, and the circuit board and the outer electric circuit can be electrically connected accurately and firmly over a long period of time. Furthermore, a mounted structure of a circuit board having high reliability which can sufficiently dealt with the use of multiple pins due to large sizing of a semiconductor element can be realized. Furthermore, simultaneous sintering with the Cu metallized layer can be performed, and since the binder can be removed efficiently, the product is of high quality and is cheap.

Circuit board

A dielectric ceramic composition having a high dielectric constant and a coefficient of thermal expansion nearly comparable with that of alumina, and a package for packaging semiconductor. The dielectric ceramic composition contains 0.1 to 0.6 parts by weight of manganese reckoned as an oxide per 100 parts by weight of chief components of the formula xTiO.sub.2 .cndot.yMgO.cndot.zSrO or of the formula xTiO.sub.2 .cndot.yMgO.cndot.zCaO wherein x, y and z are numerals that lie within given ranges. The package for packaging semiconductor comprises a package body composed of alumina and having a semiconductor-mounting portion, and a capacitor made up of a dielectric layer and an electrode layer provided on said semiconductor-mounting portion, wherein the dielectric layer is composed of the TiO.sub.2 --MgO--SrO--MnO.sub.2 -type dielectric ceramic or the TiO.sub.2 --MgO--CaO--MnO.sub.2 -type dielectric ceramic.

Dielectric ceramic composition and package made of the same composition

A package for a semiconductor device comprising (i) a high dielectric layer composed of an alumina particles, a high permittivity-imparting agent in particles selected from (a) W or Mo, (b) Re and (c) zirconia and a glass plase comprising alumina and at least one component selected from silica, alkaline earth metal components, and rare earth device components present in their grain boundaries, (ii) a pair of electrode layers comprising as a main component a metal selected from W and Mo provided on both sides of the high dielectric layer, and (iii) insulation layers composed of alumina particles and a glass phase composed of alumina and at least one component selected from silica, alkaline earth metal components and rare earth device components, the insulation layers being provided so as to sandwich the electrode layers and the dielectric layer.

High dielectric layer-containing alumina-based wiring substrate and

Growing community of inventors

Kokubu, Japan

Takeshi Kubota