BARRIER SEQUENCE FOR USE IN COPPER INTERCONNECT METALLIZATION

A method patterns at least one opening in a low-K insulator layer of a multi-level integrated circuit structure, such that a copper conductor is exposed at the bottom of the opening. The method then lines the sidewalls and the bottom of the opening with a first Tantalum Nitride layer in a first chamber and forms a Tantalum layer on the first Tantalum Nitride layer in the first chamber. Next, sputter etching on the opening is performed in the first chamber, so as to expose the conductor at the bottom of the opening. A second Tantalum Nitride layer is formed on the conductor, the Tantalum layer, and the first Tantalum Nitride layer, again in the first chamber. After the second Tantalum Nitride layer is formed, the methods herein form a flash layer comprising a Platinum group metal on the second Tantalum Nitride layer in a second, different chamber. After this processing, the structure can be moved to a third chamber where copper is deposited on the flash layer in the opening until the opening is coated with copper in a third chamber.