Heterogeneous Integration at Fine Pitch (≤ 10 µm) Using Thermal Compression Bonding

The scaling of package and circuit board dimensions is central to heterogeneous system integration. We describe our solderless direct metal-to-metal low pressure (<; 70 MPa) and low temperature (<; 250 °C) thermal compression bonding (TCB) technique and present preliminary results of dielet (4 - 25 mm
²
area) attach to a rigid Silicon Interconnect Fabric (SiIF) with up to two levels of wiring (2 - 10 μm pitch). Dielets were attached at a pitch ≤ 10 μm with an inter-dielet spacing of ≤ 100 μm. We show an effective specific contact resistance of <; 1 Ω-μm
²
and shear strength of > 20 MPa. The combined reduction of dielet interconnect pitch, dielet-to-dielet spacing and trace pitch will enable a Moore's law for packaging.