PURPOSE: To protect a bonding pad against corrosion by composing an insulation protective film of an organic resin film and covering the exposed surface of the bonding pad except the part being bonded to a bonding wire.

CONSTITUTION: The semiconductor device comprises a metal wiring pattern including a bonding pad 14 formed on a semiconductor substrate 1 through insulation films 2, 3, an insulation protective film 15 covering the metal wiring pattern, and a bonding wire 6 being bonded to the bonding pad 14. In particular, the insulation protective film 15 is composed of an organic resin film and covers the exposed surface of the bonding pad 14 except the part being bonded to the bonding wire 6. In other words, the exposed part of the bonding pad 14 is covered with the insulation protective film 15 by subjecting the organic resin film to heat treatment at a temperature higher than the glass transition point thereof thereby fluidizing the organic resin film to wet the surface of the bonding pad. This method blocks moisture for a resin package and protects the bonding pad 14 against corrosion.