According to the method for manufacturing a semiconductor device, a surface of a lower insulating film (55) is planarized by CMP or the like, and an upper insulating film (56) and a protective metal film (59) are formed on the lower insulating film (55). Accordingly, the upper insulating film (56) and the protective metal film (59) are formed in such a manner they have an excellent coverage and the water/hydrogen blocking capability of the upper insulating film (56) and the protective metal film (59) is maximized.