Package on package (PoP) devices and methods of packaging semiconductor dies are disclosed. A PoP device includes a first packaged die and a second packaged die coupled to the first packaged die. Metal stud bumps are disposed between the first packaged die and the second packaged die. The metal stud bumps include a stick region, a first ball region coupled to a first end of the stick region, and a second ball region coupled to a second end of the stick region. The metal stud bumps include a portion that is partially embedded in a solder joint.