Ultra-Thinned Individual SOI Die ACF FC Bonded on Rigid and Flex PCB

Abstract

We have developed a straightforward die-level thinning process suitable for Silicon-On-Insulator (SOI) dies. The process has been demonstrated on SOI CMOS die assembled on rigid and flexible PCBs using previously-developed anisotropic conductive adhesive flip-chip method. Unlike standard wafer-level thinning processes, in the demonstrated process the full thickness SOI die is directly mounted on PCB and after that thinned. The demonstrated process is simple and robust; it comprises fewer process steps compared to conventional die thinning process. The ultra-thinning process has no effects on the assembly integrity and device performance.