US Patent 7911044 RF module package for releasing stress

The present invention discloses a structure of package comprising: a substrate with a die receiving through hole; a base attached on a lower surface of the substrate; a die disposed within the die receiving through hole and attached on the base; a dielectric layer formed on the die and the substrate; a re-distribution layer (RDL) formed on the dielectric layer and coupled to the die; a protection layer formed over the RDL; and pluralities of pads formed on the protection layer and coupled to the RDL. The RDL is made from an alloy comprising Ti/Cu/Au alloy or Ti/Cu/Ni/Au alloy.