Massive Orthogonal Stacking Assembly of IC (Mosaic) Cube with Inductive Coupling for Exascale Memory Applications

A novel massive orthogonal stacking assembly of IC (MOSAIC) cube with inductive coupling is proposed and demonstrated. Thermal simulation is done to confirm thermal performance of the MOSAIC cube. Mechanical simulation is also performed to identify stress concentration points which may cause reliability issues. Inductive coupling is employed to enable contactless communication between the cube and base chip. This approach not only simplifies the assembly process but also mitigates package reliability issues. The MOSAIC cube assembly process is developed. An 8-die stacked cube is successfully demonstrated with 0.18 um CMOS test vehicles. The 3D die locations in a cube are precisely measured using newly developed metrology. MOSAIC enables ultra high-density integration, high thermal performance, and simple assembly, and it can be scaled to stack multiple tens of dies without compromising thermal performance.