Core-shell ball grid array materials for large form factor integrated circuit packages

An apparatus, comprising:

• a first metallization structure of a host component;
• a second metallization structure of an integrated circuit (IC) device;
• and
• an interconnect structure coupling the first metallization structure and the second metallization structure, the interconnect structure comprising:
• an inner metal core comprising tin, silver, and copper;
• and
• a metal cladding surrounding the inner metal core, the metal cladding comprising tin and bismuth.

An apparatus, comprising:

• a microelectronics board;
• an integrated circuit (IC) package comprising one or more IC devices;
• and
• an interconnect structure electrically coupling the microelectronics board to the IC package, the interconnect structure comprising:
• an inner core having a first melting point;
• and
• a cladding surrounding the inner core, the cladding having a second melting point, wherein the first melting point is not less than 40° C. greater than the second melting point.