US Patent 7906376 Magnetic particle-based composite materials for semiconductor packages

A semiconductor package is described. The semiconductor package includes a substrate and an integrated heat spreader disposed above and coupled with the substrate. A cavity is disposed between the substrate and the integrated heat spreader. A semiconductor die is disposed above the substrate and in the cavity. An array of first-level solder joints is disposed between the substrate and the semiconductor die. A layer of magnetic particle-based composite material is also disposed in the cavity.