Manufacturing method of copper interconnection structure

The invention relates to the technical field of semiconductor integrated circuit manufacturing, in particular to a manufacturing method of a copper interconnection structure. The manufacturing method of the copper interconnection structure comprises the following steps that a semiconductor interconnection medium structure is provided, an interconnection wire groove is formed in the interconnection medium structure, and the interconnection wire groove extends downwards from the upper surface of the interconnection medium structure; forming a liner layer in the interconnection wire slot; depositing metal copper in the interconnection wire duct with the liner layer; planarizing the surface layer of the metal copper through a chemical mechanical grinding process; bombarding reducing gas plasma on the planarized metal copper surface to remove copper oxide on the planarized metal copper surface; and forming an upper interlayer dielectric layer on the semiconductor interconnection dielectric structure. According to