Heat dissipation structure for integrated circuit packages

A package structure, comprising:

• a package substrate;
• an interposer bonded to the package substrate by way of first-type bumps;
• a first underfill surrounding the first-type bumps;
• a first die and a second die bonded to the interposer by way of second-type bumps;
• a second underfill surrounding the second-type bumps;
• a metal layer interfacing the interposer, the second underfill, sidewalls of the first die, and sidewalls of the second die;
• a first molding material over the metal layer;
• a thermal interface material disposed over the first molding material, the metal layer, the first die, and the second die;
• and
• a second molding material over the package substrate and surrounding the first underfill and the first molding material.

A package structure, comprising:

• a package substrate;
• an interposer bonded to the package substrate by way of first-type bumps;
• a first underfill surrounding the first-type bumps;
• a first die and a second die bonded to the interposer by way of second-type bumps;
• a second underfill surrounding the second-type bumps;
• a metal layer interfacing the interposer, the second underfill, sidewalls of the first die, and sidewalls of the second die;
• a first molding material over the metal layer;
• a second molding material over the package substrate and surrounding the first underfill and the first molding material;
• and
• a thermal interface material disposed over the first molding material, the second molding material, the metal layer, the first die, and the second die,
• wherein the metal layer comprises titanium-copper, copper, or gold.