A device and methods of forming the device are disclosed. A substrate with a circuits component and a dielectric layer with interconnects is provided. A pad level dielectric layer is formed over the dielectric layer. A primary passivation layer is formed over the pad level dielectric layer with pad interconnects. The substrate is subjected to an alloying process. During the alloying process, the primary passivation layer prevents or reduces formation of hillocks on surfaces of the pad interconnects to improve surface smoothness of the pad interconnects. Pad openings are formed in the pad level dielectric layer to expose top surfaces of the pad interconnects. A cap dielectric layer is formed on the substrate and lines the primary passivation layer as well as the exposed top surfaces of the pad interconnects. A final passivation layer is formed on the substrate and covers the cap dielectric layer. The final passivation layer is patterned to form final passivation openings corresponding to the pad openings.