| abstract |
[57] An alloy formed by diffusing Sn contained in solder constituting a ball electrode solder into Cu of metal wiring is brittle and has low bonding strength. There was a problem that the alloy layer formed at the boundary portion of the steel was easily broken. An external terminal 1 is partially formed on a surface of a semiconductor element 8. The metal wiring 11 forming 0 and the external terminal 10 of the metal wiring 11 are opened on the surface side of the semiconductor element 8 to form a resin film 12 (solder resist), and the resin film 12 is formed on the external terminal 10. The metal material filling portion 13 is formed with a thickness substantially equal to or greater than the thickness of the resin film 12. |