Patent attributes
A microelectronic element and a related method for fabricating such is provided. The microelectronic element comprises a contact pad overlying a major surface of a substrate. The contact pad has a composition including copper at a contact surface. A passivation layer is also provided overlying the major surface of the substrate. The passivation layer overlies the contact pad such that it exposes at least a portion of the contact surface. A plurality of metal layers arranged in a stack overlie the contact surface and at least a portion of the passivation layer. The stack includes multiple layers, which can have different thicknesses and different metals, with the lowest layer including titanium (Ti) and nickel (Ni) in contact with the contact surface.
