The present disclosure provides a semiconductor package, which includes a substrate, a passivation layer, a post-passivation interconnect (PPI) having a top surface; and a conductive structure. The top surface of the PPI includes a first region receiving the conductive structure, and a second region surrounding the first region. The second region includes metal derivative transformed from materials made of the first region. The present disclosure provide a method of manufacturing a semiconductor package, including forming a first flux layer covering a portion of a top surface of a PPI; transforming a portion of the top surface of the PPI uncovered by the first flux layer into a metal derivative layer; removing the first flux layer; forming a second flux layer on the first region of the PPI; dropping a solder ball on the flux layer; and forming electrical connection between the solder ball and the PPI.