There is provided a solution to the problem of the poor adhesion in the pad portion while inhibiting the dishing in the pad portion. An SiON film, which covers insulating areas and has an opening above Cu pad areas, is formed, and a barrier metal film is formed in the opening of the SiON film. Such constitution provides the structure, in which the upper portion of the interfaces between the Cu pad areas and the insulating areas are covered by the SiON film.