Patent ID: 7545040

Claim:
A copper alloy for wiring formed by a manufacturing method comprising the steps of: forming a polycrystalline Cu film; forming, on the polycrystalline Cu film, a layer made of an additional element to be added into the polycrystalline Cu film; diffusing the additional element from the additional element layer into the polycrystalline Cu film via crystal grain boundaries to form a polycrystalline copper alloy; and simultaneously therewith performing gettering of oxygen in the polycrystalline Cu film into the additional element layer, wherein the additional element is at least one element selected from a group consisting of Ti (titanium), Zr (zirconium), Hf (hafnium), Cr (chromium), Co (cobalt), Al (aluminum), Ni (nickel), and Mg (magnesium), and concentration of the additional element is, at grain boundaries of crystal grains composing the polycrystalline copper alloy and in vicinities of grain boundaries, higher than that of the inside of the crystal grains, a barrier metal film containing a barrier metal is formed to surround the polycrystalline copper alloy, and concentration of the additional element is, at the interface between the polycrystalline copper alloy and the barrier metal film and in vicinities of said interface, higher than that of the inside of the crystal grains, and the barrier metal in the barrier metal film has not been oxidized.