Integrated circuit packages and methods of forming the same

A device comprising:

• a package component comprising a first integrated circuit die, a second integrated circuit die, and an encapsulant encapsulating the first integrated circuit die and the second integrated circuit die;
• a back-side metal layer on a back-side of the package component, the back-side metal layer comprising gold;
• an indium thermal interface material on the back-side metal layer, a gold-containing intermetallic compound at an interface between the back-side metal layer and the indium thermal interface material;
• a lid, the indium thermal interface material on the lid, an interface between the indium thermal interface material and the lid being free of gold-containing intermetallic compounds;
• and
• a package substrate connected to the package component, the lid being adhered to the package substrate.

A device comprising:

• a plurality of integrated circuit dies;
• a package component comprising the plurality of integrated circuit dies and conductive connectors connected to the plurality of integrated circuit dies, the conductive connectors at a front-side of the package component;
• a back-side metal layer on a back-side of the package component;
• a flux on the back-side metal layer, the flux being over back-sides of the plurality of integrated circuit dies with a gap between sections of the flux;
• an indium thermal interface material on the flux, the indium thermal interface material having a width larger than a width of the package component, the indium thermal interface material having gaps in regions outside of where the indium thermal interface material overlies the plurality of integrated circuit dies;
• a lid on the indium thermal interface material;
• a package substrate connected to the conductive connectors, the lid being adhered to the package substrate;
• and
• an underfill between the package substrate and the package component.