US Patent 11387224 Phase change material in substrate cavity

A semiconductor device package structure is provided. The semiconductor device package structure includes a substrate having a cavity, and phase change material within the cavity. In an example, the phase change material has a phase change temperature lower than 120 degree centigrade. A die may be coupled to the substrate. In an example, the semiconductor device package structure includes one or more interconnect structures that are to couple the die to the phase change material within the cavity.