MULTILAYER WIRING SUBSTRATE

摘要

PURPOSE: A multilayer wiring substrate is provided to prevent the damage of a solder layer due to the thin thickness of the solder layer by supplying enough solder paste on the upper surface of a conductive pad. CONSTITUTION: The upper surface(62A) of a second conductive pad(62) includes a concave central section(62A-1). A solder layer(64) is formed to cover the upper surface and the side surface(62B). The second conductive pad is projected from the surface of a second resist layer(42). The solder layer is spread by flux to remove oxide on the upper part of the second conductive pad. The concave central section of the second conductive pad maintains enough flux.