The present invention generally provides a metallization process for
forming a highly integrated interconnect. More particularly, the present
invention provides a dual damascene interconnect module that incorporates
selective chemical vapor deposition aluminum (CVD Al) via fill with a
metal wire, preferably copper, formed within a barrier layer. The
invention provides the advantages of having copper wires with lower
resistivity (greater conductivity) and greater electromigration
resistance than aluminum, a barrier layer between the copper wire and the
surrounding dielectric material, void-free, sub-half micron selective CVD
Al via plugs, and a reduced number of process steps to achieve such
integration.