Abstract: A composite multi-layer substrate comprising a flat plate-like core member formed of a material having an excellent electric conductivity, an excellent heat conductivity, and a high rigidity, a front resin layer and a rear resin layer covering at least the front and rear surfaces of the core member, and a bottomless hole formed in the core member through the front and rear sides of the core member, wherein an electronic component is installed in the bottomless hole, whereby since the strength of the composite multi-layer substrate can be assured by the rigidity of the core member, conventional prior art glass cloth can be eliminated, deterioration in the electric characteristics caused by ion migration can be avoided and will result in reduced production cost.

Abstract: A multilayer printed wiring board (PWB) including via holes with satisfactory quality without defective shapes like swelling or recession on the end faces is provided. The multilayer PWB includes a build-up board of plural insulation layers as the main structure. In each of the insulation layers, via holes (columnar conductors) for electrically connecting between conductor circuits on the base layer or adjacent layers are formed. The via holes are formed by patterning metal foil with conductivity. The height “H” of the via holes (dimension in the thickness direction of the via hole forming layer) depends on the thickness “D” of the original metal foil only. Accordingly, the via holes can be formed without carrying out filling with conductive paste or electrolytic plating. Thus, multilayer PWB having via holes with satisfactory quality without defective shapes like swelling or recession on the end faces can be manufactured.

Abstract: A multilayer printed wiring board (PWB) including via holes with satisfactory quality without defective shapes like swelling or recession on the end faces is provided. The multilayer PWB includes a build-up board of plural insulation layers as the main structure. In each of the insulation layers, via holes (columnar conductors) for electrically connecting between conductor circuits on the base layer or adjacent layers are formed. The via holes are formed by patterning metal foil with conductivity. The height “H” of the via holes (dimension in the thickness direction of the via hole forming layer) depends on the thickness “D” of the original metal foil only. Accordingly, the via holes can be formed without carrying out filling with conductive paste or electrolytic plating. Thus, multilayer PWB having via holes with satisfactory quality without defective shapes like swelling or recession on the end faces can be manufactured.

Abstract: A composite multi-layer substrate comprising a flat plate-like core member formed of a material having an excellent electric conductivity, an excellent heat conductivity, and a high rigidity, a front resin layer and a rear resin layer covering at least the front and rear surfaces of the core member, and a bottomless hole formed in the core member through the front and rear sides of the core member, wherein an electronic component is installed in the bottomless hole, whereby since the strength of the composite multi-layer substrate can be assured by the rigidity of the core member, conventional prior art glass cloth can be eliminated, deterioration in the electric characteristics caused by ion migration can be avoided and will result in reduced production cost.

Abstract: A multilayer printed wiring board (PWB) including via holes with satisfactory quality without defective shapes like swelling or recession on the end faces is provided. The multilayer PWB includes a build-up board of plural insulation layers as the main structure. In each of the insulation layers, via holes (columnar conductors) for electrically connecting between conductor circuits on the base layer or adjacent layers are formed. The via holes are formed by patterning metal foil with conductivity. The height “H” of the via holes (dimension in the thickness direction of the via hole forming layer) depends on the thickness “D” of the original metal foil only. Accordingly, the via holes can be formed without carrying out filling with conductive paste or electrolytic plating. Thus, multilayer PWB having via holes with satisfactory quality without defective shapes like swelling or recession on the end faces can be manufactured.

Abstract: Components having different heights are installed in a multilayer substrate using a metal core layer formed by bonding a plurality of metal layers. The metal core layer includes through-holes and a spot-faced portion. Passive components and an active component are disposed in the through-holes and the spot-faced portion, respectively. These components are connected to conductive patterns formed on wiring layers, with connecting vias therebetween. Contact faces of each component with the connecting vias are controlled so as to be disposed at the same level with the metal layers.