Multilayer printed circuit board and manufacture thereof

Abstract

Abstract PURPOSE:To simultaneously perform excellent adhesive strength of a conductor layer with an insulating layer and viahole connection reliability by forming a glossy face on an electrically connecting section through a following conductor layer and a viahole of a conductor layer having a precedingly formed roughed surface by smoothing. CONSTITUTION:A circuit board having conductor patterns 1 is dipped in alkaline sodium chlorite solution, then dipped in alkaline aqueous reducing agent solution, and a roughed face 3 is formed on the surface of the conductor pattern. After a photosensitive resin insulating layer is formed, a photomask film is brought into close contact, exposed and developed to form a heat resistant resin insulating layer 4 having an opening 10. The board is dipped in an oxidizer to form a roughed face 5 on the surface of the interlayer resin insulating layer 4. Then, it is softly etched to form a smooth face 6 on the conductor pattern. Thereafter, an electroless copper plating film 7 is provided on a board 2 in which the layer 4 is roughed. These steps are repeated to obtain a build-up multilayer circuit board having four interconnection layers is obtained.

Inventors

• 👤 Akira Enomoto
• 👤 亮 榎本
• 👤 Yoshikazu Sakaguchi
• 👤 坂口　芳和
• 👤 Motoo Asai
• 👤 元雄 浅井

Bibliographic Details