Patent ID: 6903008

Claim:
A method for forming a semiconductor element, comprising: forming a groove having a bottom wall and side walls in a surface of an insulating film; sequentially forming a first layer and a second layer over the surface of the insulating film and over the bottom wall and side walls of the groove in a first chamber, wherein the first layer is made of a high melting-point metal and the second layer is made of a nitride of the high melting-point metal, wherein a thickness of the first layer is formed to be thinner than a thickness of the second layer, wherein a combined thickness of the first and second layers formed over the side walls of the groove is thinner than a combined thickness of the first and second layers formed over the surface of the insulating film, and wherein the combined thickness of the first and second layers formed over the side walls of the groove is thinner than a combined thickness of the first and second layers formed over the bottom wall of the groove; forming a conductive layer over the surface of the insulating film and within the groove in a second chamber, wherein the conductive layer includes copper, and wherein the first and second layers are interposed between the conductive layer and the insulating film; and chemically and/or mechanically polishing the conductive layer to remove the conductive layer formed over the surface of the insulating film.