Metal wire for a semiconductor device formed with a metal layer without voids therein and a method for forming the same

A method for forming a metal wiring of a semiconductor device comprising the steps of:

• forming an insulation layer provided with a damascene pattern over a semiconductor substrate;
• forming a Ru layer on the insulation layer provided with the damascene pattern;
• forming a first metal layer on the Ru layer by a sputtering method in order to surround both-side upper portion of the damascene pattern;
• forming a RuO2 layer on a surface of the damascene pattern and an Al deposit-inhibiting layer on both-side of the upper portion of the damascene pattern by oxidizing the first metal layer and the Ru layer so as to form a diffusion barrier layer composed of the RuO2 layer and the Al deposit-inhibiting layer;
• and
• forming a second metal layer including Al for wiring on the diffusion barrier layer by MOCVD method in order to fill the damascene pattern.