| 摘要 |
PROBLEM TO BE SOLVED: To easily remove a Cu oxide formed on the surface of a Cu interconnection and thereby to reduce the wire resistance of the Cu interconnection including vias in the formation of the Cu interconnection using a damascene method. SOLUTION: In an insulation film 2 formed on a semiconductor substrate 1, trenches 3 for interconnections are formed. Then, on the entire surface of the insulation film 2 including the trenches 3 for interconnections, a TaN film 4 and a sputter Cu film 5 are formed by sputtering. Next, the trenches 3 for interconnections are filled with an electrolytic plating Cu film 6 by electrolytic plating with the sputter Cu film 5 as a seed layer to form a film 7 for a Cu interconnection which is formed of the sputter Cu film 5 and the electrolytic plating Cu film 6. Thereafter, unnecessary parts of the film 7 for a Cu interconnection and the TaN film 4 on the insulation film 2 are polished and removed by CMP to form a Cu interconnection 7a and barrier layers 4a in the trenches 3 for interconnections. Then, the semiconductor substrate 1 is heat-treated in a vacuum to remove a Cu oxide formed on the surface of the Cu interconnection 7a. Then, without exposing the semiconductor substrate 1 to an oxidizing atmosphere, a protective film 8 is formed on the Cu interconnection 7a. COPYRIGHT: (C)2003,JPO
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