Semiconductor apparatus and method of making the same

A semiconductor apparatus, comprising:

• an interconnect substrate having a first major surface;
• a first semiconductor device having a second major surface and mounted to the interconnect substrate, the second major surface opposing the first major surface;
• a second semiconductor device having a third major surface and a fourth major surface and mounted to the first semiconductor device, the third major surface opposing the first major surface, the fourth major surface opposing the second major surface;
• a through hole formed through the interconnect substrate at a position overlapping the second semiconductor device in a plan view taken in a thickness direction of the interconnect substrate;
• and
• a heatsink member disposed in surface-to-surface contact with part of the third major surface, at least a part of the first major surface, and at least a part of a sidewall surface of the through hole,
• wherein in the plan view, the heatsink member is situated inside an outer perimeter of the second semiconductor device and smaller than the second semiconductor device,
• wherein the heatsink member includes a first portion and a second portion, the first portion being disposed outside the through hole, and the second portion being disposed inside the through hole, the first portion being wider than the second portion in a direction parallel to the first major surface, the first portion being in surface-to-surface contact with at least the part of the first major surface, the second portion being in surface-to-surface contact with at least the part of the sidewall surface of the through hole, and
• wherein an upper portion of the through hole is filled with the second portion of the heatsink member, and a lower portion of the through hole is hollow.