CIRCUIT BOARD AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a circuit board and its manufacturing method which selectively compresses portions of a conductive paste to stably enable the interlayer connection. SOLUTION: The circuit board has metal foils 2, 3 laid on both sides of an electric insulation layer 1 and the foils are electrically connected by filling a conductive paste 4 in vias connecting through the thickness of an electric insulation layer 1. A part of at least one side of each metal foil 2, 3 is buried in the insulation layer 1 and other parts are laid on the insulation layer. Bumps of the metal foil 3 are formed e.g. by half etching a thicker copper foil.