Abstract: A method of manufacturing a multi-layer circuit board including preparing a laminated member formed of (i) a core circuit board having a circuit pattern thereon and (ii) a prepreg sheet having a through-hole filled with conductive paste, forming a laminated structure such that the laminated member is sandwiched by lamination plates, and applying heat and pressure to the laminated structure. According to this method, selecting a lamination plate that has a thermal expansion coefficient that is equivalent to that of a core circuit board will protect the conductive paste from distortion, thereby offering a high-quality multi-layer circuit board having a reliable connection resistance.

Abstract: A method of manufacturing a multi-layer circuit board having the following steps: preparing a laminated member formed of a core circuit board having a circuit pattern thereon and a prepreg sheet having a through-hole filled with conductive paste; forming a laminated structure in a manner that the laminated member is sandwiched by lamination plates; and applying heat and pressure to the laminated structure. According to the method, selecting a lamination plate so as to have thermal expansion coefficient equivalent to that of a core circuit board can protect conductive paste from distortion, thereby offering a high-quality multi-layer circuit board with reliable connection resistance.

Abstract: A pre-preg sheet includes a substrate and a resin impregnated in the substrate. A first metal foil is placed on the pre-preg sheet to provide a laminated body. The laminated body is put in a heating device having a temperature maintained at a temperature close to a softening temperature of the resin. The laminated body is compressed at the temperature at a predetermined pressure. The first metal foil is bonded to the pre-preg sheet of the laminated body and hardening the resin, thus providing a circuit board. This method provides a stable resistance of a conductive paste filing a through-hole in the pre-preg sheet to be compressed at a small rate.

Abstract: A pre-preg sheet including a substrate and a resin impregnated in the substrate is provided. A first metal foil is placed on the pre-preg sheet to provide a laminated body. The laminated body is put in a heating device having a temperature maintained at a temperature close to a softening temperature of the resin. The laminated body is compressed at the temperature at a predetermined pressure. The first metal foil is bonded to the pre-preg sheet of the laminated body and hardening the resin, thus providing a circuit board. This method provides a stable resistance of a conductive paste filling a through-hole in the pre-preg sheet to be compressed at a small rate.

Abstract: The present invention relates to ceramics and a method for making ceramics having very little dimensional change after sintering and high dimensional accuracies, so that the characteristics of inorganic functional material are fully maintained and utilized. The ceramics of the present invention comprise grains of inorganic functional material and grains of complex oxide. The pores existing between said grains of inorganic functional material are filled with said grains of complex oxide produced by a sintering reaction between an oxidized metal and an inorganic compound.

Abstract: The present invention relates to ceramics and a method for making ceramics having very little dimensional change after sintering and high dimensional accuracies, so that the characteristics of inorganic functional material are fully maintained and utilized. The ceramics of the present invention comprise grains of inorganic functional material and grains of complex oxide. The pores existing between said grains of inorganic functional material are filled with said grains of complex oxide produced by a sintering reaction between an oxidized metal and an inorganic compound.