In a method for manufacturing a semiconductor device, a first Ti film, a titanium nitride (TiN) film, a second Ti film, a first aluminum (Al) film and a second Al film are formed sequentially in a contact hole formed in a second interlayer insulating film and on a Cu wire. The first titanium (Ti) film is formed so that a ratio of a thickness of a first portion of the first Ti film on a bottom face of the contact hole to a thickness of a second portion of the first Ti film on the second interlayer insulating film becomes equal to or smaller than 5/100. Moreover, the second Al film is formed using an aluminum reflow method, in which the second Ti film and the first Al film are alloyed with each other to form an Al—Ti alloy film.