| abstract |
In one embodiment, a copper interconnect structure is formed by depositing a dielectric layer ( 28 ) on a semiconductor substrate ( 10 ). The dielectric layer ( 28 ) is then patterned to form interconnect openings ( 29 ). A layer of copper ( 34 ) is then formed within the interconnect openings ( 29 ). A portion of the copper layer ( 34 ) is then removed to form copper interconnects ( 39 ) within the interconnect openings ( 29 ). A copper barrier layer ( 40 ) is then formed overlying the copper interconnects ( 39 ). Adhesion between the copper barrier layer ( 40 ) and the copper interconnects ( 39 ) is improved by exposing the exposed surface of the copper interconnects ( 39 ) to a plasma generated using only ammonia as a source gas. |