CRACK-RESISTANT SOLDER JOINT, ELECTRONIC COMPONENT SUCH AS CIRCUIT SUBSTRATE HAVING THE SOLDER JOINT, SEMICONDUCTOR DEVICE, AND MANUFACTURING METHOD OF ELECTRONIC COMPONENT

摘要

A crack-resistant solder joint is provided to form a structure in which a crack seldom occurs in a solder joint by controlling the depth of a concave part position in a part of a land on which a solder joint process is performed and the thickness of nickel plating performed on the land part. A solder joint includes a concave part(113) and at least one metal layer stacked on the surface of the concave part wherein the concave part is recessed with respect to the surface of a substrate(111). A position between the interface of the metal layer and a tin alloy layer formed on the surface of the metal layer in soldering the metal layer and a plane including a reference surface of an electrode included in an electronic component goes amiss. The metal layer can be higher than the reference surface so that the surface of the metal layer is formed outside the concave part.