A High Throughput Two- Stage Die-to-Wafer Thermal Compression Bonding Scheme for Heterogeneous Integration

In this work, we demonstrate for the first time a two-stage high throughput fine-pitch die-to-wafer Copper-Copper (Cu) thermal compression bonding (TCB) technique, which has a throughput of > 300 units-per-hour (UPH), with the potential to increase the throughput to 1100 UPH. We have optimized the bonding for high throughput, high overlay accuracy and low contact resistance with a die-to-substrate bump pitch of <= 10 mu m extendible to similar to 7 mu m pitch. The average shear force per 2x2 mm(2) die after high throughput TCB is > 110 N. The average specific contact resistance of the Cu-Cu contact is 1.24 X 10(-9) Omega center dot cm(2), comparable to the lowest reported in Cu/SiO2 hybrid bonding. The simplicity of TCB compared to hybrid bonding (HB) makes it a preferred approach for heterogeneous integration for 3D stacking, interposers, and the Silicon Interconnect Fabric (Si-IF) down to similar to 7 mu m bonding pitches.