Patent 7924529 was granted and assigned to Nitto Denko on April, 2011 by the United States Patent and Trademark Office.
A stepped-part 4b with a lower tip side is formed on the top face of a pattern end 4, and a lower face 4c thereof is used as a plane on which a solder ball 7 is provided. One or more protrusions 4d made of a swollen conductive layer are formed on the lower face to limit displacement of the solder ball in the tip direction and the both side directions. The solder ball is held by the protrusions to suppress deviation of the solder ball.