Manufacture of printed wiring substrate

Abstract

Abstract PURPOSE:To improve reliability of a through-hole by removing, prior to drilling a punching hole in a substrate, a copper foil and a base material of a predetermined region including a punching hole formation scheduled part by drilling. CONSTITUTION:Prior to drilling a punching hole 4 through a substrate 9, a drilling hole 13 is made at a location on the substrate 1 including a punching hole 4 formation scheduled part with a size larger than the punching hole 4, and thereafter unhardened resin 14 is poured into the drilling hole 13 and hardened to fill the hole therewith. Thereafter, the punching hole 4 is made through the resin 14 which is filled with conductive paste 5. Accordingly, a base material 3 and copper foils 1, 2 in a predetermined region including the punching hole 4 formation scheduled part are removed, so that burrs and deformation on the copper foils 1, 2 are prevented from being produced upon drilling the punching hole 4 after the resin 14 is filled, and the thickness of the paste 5 is made uniform from a corner part to junctions between the paste 5 and the copper foils 1, 2. Hereby, reliability of the through-hole is improved.

Inventors

• 👤 Yukio Matsuno
• 👤 松野　幸男

Bibliographic Details