NIckel Alloy for Semiconductor Packaging

A method for fabricating a packaged semiconductor die, comprising:

• providing a fully processed semiconductor wafer that includes more than one semiconductor die, the semiconductor wafer having a front side containing copper leads of said more than one semiconductor die and a back side that is opposite to said front side;
• etching selected portions of a protective overcoat layer from said fully processed semiconductor wafer to expose a top surface of said copper leads;
• forming a copper seed layer over said front side of said semiconductor wafer;
• coating said front side of said semiconductor wafer with a nickel alloy that includes tungsten and cerium (NiWCe);
• removing said copper seed and said nickel alloy located over said protective overcoat;
• singulating said semiconductor wafer to create said semiconductor die having a front side containing said leads of said semiconductor die and a back side that is opposite to said front side;
• attaching said back side of said semiconductor die onto a die pad;
• wire bonding said leads of said semiconductor die to leads of a lead frame;
• and encapsulating said semiconductor die, said wire bonds, and portions of said die pad and said leads of said lead frame in molding compound.