| 摘要 |
PURPOSE:To improve reliability of continuity between conductive layers and to enable manufacturing of a multilayer circuit substrate in small cost, by forming a copper foil circuit, whose external surface is roughed, on an insulation substrate and forming an insulating layer thereon and printing conductive paste on the insulating layer so as to cross over a copper foil surface which is exposed on a via hole so that a second conduction circuit is formed. CONSTITUTION:A prescribed copper foil circuit 3, whose external surface at least is roughed, is formed on an insulating substrate 2, and a first insulating layer 5 is formed thereon. In succession, conductive paste is printed across a copper foil surface exposed on a via hole 4 so that a second conductive circuit 6 is formed and further a second insulating layer 8 is formed as required. For example, copper foil 1 roughed on its both surfaces are stuck on the surface of the insulation substrate 2 to prepare a copper stuck substrate, and this copper foil 1 is etched to form a first conductive layer 3. In succession, the via hole 4 is made to remain to form the first insulating layer 5, and the conductive paste is printed and hardened on the layer 5 to form the second conductive circuit 6. Further, plating is performed to form a plated film 7, and the plated film 7 is coated with insulating paste as required to form the second insulating layer 8. |
