MULTILAYER WIRING BOARD AND METHOD FOR MANUFACTURING MULTILAYER WIRING BOARD

摘要

Disclosed is a multilayer wiring board having via-hole conductors for connecting a first copper wiring and a second copper wiring, the via-hole conductor including a metal portion and a resin portion. The metal portion includes a first metal region including a link of copper particles as a path for electrically connecting the first and second copper wirings; a second metal region mainly composed of at least one selected from tin, a tin-copper alloy, and a tin-copper intermetallic compound; and a third region mainly composed of bismuth. The copper particles forming the link are in plane-to-plane contact with one another. At least one of the first copper wiring and the second copper wiring is in plane-to-plane contact with the copper particles, and the portion where there is such a plane-to-plane contact is covered with at least a part of the second metal region.