The invention relates to a substrate (1) for electrical circuits comprising at least one first composite layer (2) which is produced by means of roll cladding and, after said roll cladding, has at least one copper layer (3) and an aluminium layer (4) attached thereon, wherein at least the surface side of the aluminium layer (4) facing away from the copper layer (3) is anodized for the generation of an anodic or insulating layer (5) made of aluminium oxide, and wherein the anodic or insulating layer (5) made of aluminium oxide is connected to a metal layer (7) or at least one second composite layer (2) or at least one paper-ceramic layer (11) via at least one adhesive layer (6, 6).

A circuit board having an insulating layer containing a low-temperature sintering ceramic material and wiring. The wiring includes a thermal via having an area of 0.0025 mm.sup.2 or more in top view thereof, the thermal via is a stack of layers of tapered conductors, each having tapered end faces, and each end face of the tapered conductors are in direct contact with the insulating layer.

The present invention is to provide a metal particle dispersion for electroconductive substrates, which has high dispersibility and dispersion stability and which is able to form a film that shows high electroconductivity after baking. Disclosed is a metal particle dispersion for electroconductive substrates, comprising metal particles, a dispersant and a solvent, wherein the dispersant is a graft copolymer having at least a constitutional unit represented by the following chemical formula (I) and a constitutional unit represented by the following chemical formula (II): ##STR00001##
(Symbols in the formulae are as described in the Description.)

A multilayer wiring substrate that can realize a higher-density wiring structure is obtained. Provided is a multilayer wiring substrate, where a multilayer body including a first insulating layer and a second insulating layer stacked on the bottom surface of the first insulating layer includes printed wiring electrodes; the printed wiring electrodes are formed by printing with and sintering conductive paste; the printed wiring electrodes respectively include first wiring electrode portions located on the second insulating layer and second wiring electrode portions respectively joined to first wiring electrode portions; and the second wiring electrode portions respectively extend into through holes and, further, are exposed at the top surface of the first insulating layer.

An Ag.sub.2OV.sub.2O.sub.5TeO.sub.2 lead-free low-melting glass composition that is prevented or restrained from crystallization by heating so as to soften and flow more satisfactorily at a low temperature contains a principal component which includes a vanadium oxide, a tellurium oxide and a silver oxide; a secondary component which includes at least one selected from the group consisting of BaO, WO.sub.3 and P.sub.2O.sub.5; and an additional component which includes at least one selected from the group consisting of oxides of elements in Group 13 of periodic table. A total component of the principal component is 85 mole percent or more in terms of V.sub.2O.sub.5, T.sub.eO.sub.2 and Ag.sub.2O. Contents of TeO.sub.2 and Ag.sub.2O each is 1 to 2 times as much as a content of V.sub.2O.sub.5. A content of the secondary component is 0 to 13 mole percent. A content of the additional component is 0.1 to 3.0 mole percent.

A shielded printed wiring board with electromagnetic wave shielding film on both sides thereof is produced by placing electromagnetic wave shielding films on the two sides of the printed wiring board, with ends thereof protruding past an end of the printed wiring board. The protruding ends of the electromagnetic wave shielding films are brought together, with an air gap therebetween, and an initial application of heat and pressure causes the ends of the electromagnetic wave shielding film to adhere to each other, but without completely curing adhesive resin components of the electromagnetic wave shielding films. Protective film layers are removed from the electromagnetic wave shielding films, followed by subsequent application of heat and pressure to complete cure of the adhesive resin and to remove the air gap.

Techniques, elements, and assemblies for high current board-level conductive pathways on printed circuit boards are provided. In one example, a method includes providing a circuit board having footprint elements that define a route between endpoints. The method includes applying solder paste onto the footprint elements, and placing modular conductive blocks along the route onto the solder paste associated with the footprint elements. The method also includes forming, by at least a solder reflow operation, an assembly comprising the circuit board and the modular conductive blocks that establishes a conductive pathway along the route with series coupling of the modular conductive blocks to each other.

A method for producing a green body includes forming a layer which contains a powder of a ceramic on a substrate, applying at least one solidifying composition on at least a part of the layer, repeating forming the layer and applying at least one solidifying composition at least one time, removing the solvent or dispersing agent at least in part for forming a green body, and removing the powder which has not bonded and thereby exposing the green body. The solidifying composition contains a dissolved or liquid organometallic compound, which has at least one atom other than C, Si, H, O, or N bonded to at least one organic moiety, an organic binding agent, and a solvent or dispersing agent.

A method of manufacturing a ceramic substrate includes the steps of preparing a ceramic paste in which a powder of at least one of a metal boride and a metal silicide is added to a raw material powder of a glass ceramic, applying the ceramic paste to a green sheet which is to become a ceramic layer after firing, applying a conductor paste which is to become a conductor trace after firing to the ceramic paste having been applied to the green sheet, and firing the green sheet carrying the ceramic paste and the conductor paste applied thereto.

A method of manufacturing a circuit substrate includes the steps of preparing a conductor paste in which a powder of at least one of a metal boride and a metal silicide is added to a powder of silver (Ag), applying the conductor paste to a surface of a ceramic substrate which has been fired, applying a glass paste to the surface of the ceramic substrate after applying the conductor paste, firing the conductor paste applied to the surface so as to form a conductor trace, and firing the glass paste applied to the surface so as to form a coating layer.