Semiconductor device and manufacturing method thereof

A manufacturing method of a semiconductor device, wherein a first protection film is formed on a semiconductor substrate expect at a portion on an electrode pad, and a protrusion electrode whose surface is coated with a coating layer is further formed on the electrode pad, comprising the steps of:

• (A) forming the protrusion electrode on the electrode pad with electroless plating;
• (B) forming a second protection film, so as to cover at least a gap at a boundary portion of the first protection film and said protrusion electrode, having an opening on a top area of said protrusion electrode except a portion around the boundary portion of said first protection film and said protrusion electrode;
• and
• (C) forming the coating layer for coating the surface of said protrusion electrode at the opening of said second protection film.

A manufacturing method of a semiconductor device, wherein a first protection film is formed on a semiconductor substrate expect at a portion on an electrode pad, and a protrusion electrode whose surface is coated with a coating layer is further formed on the electrode pad, comprising the steps of:

• (a) removing oxide film on a surface of the electrode pad composed of or mainly composed of Al;
• (b) forming Zn on the surface of the electrode pad through displacement reaction;
• (c) forming the protrusion electrode with electroless plating of Ni or Ni alloy;
• (d) forming a second protection film so as to cover the first protection film and said protrusion electrode;
• (e) forming an opening by removing said second protection film so as to reveal a top area of said protrusion electrode except a portion around the boundary portion of said first protection film and said protrusion electrode;
• and
• (f) forming the coating layer with displacement Au plating, for coating the top area of said protrusion electrode at a portion not covered with said second protection film.