Patent ID: 6992389

Claim:
A barrier for use in an interconnect, the barrier comprising: a nickel-rich nickel-copper (NiCu) layer electrically connected to a device terminal of the interconnect, the device terminal including a recess for receiving the nickel-rich nickel-copper layer, the nickel-rich layer including a higher percentage of nickel than copper; and a copper-rich nickel-copper (NiCu) layer electrically connected to the nickel-rich NiCu layer and a solder joint of the interconnect, the copper-rich NiCu layer including a higher percentage of copper than nickel further comprising an intermediate alloy layer between the nickel-rich NiCu layer and the copper-rich NiCu layer; wherein the intermediate alloy layer includes a higher percentage of copper than the nickel-rich NiCu layer and a higher percentage of nickel than copper-rich NiCu layer.