Back-end compatibility of bonding and thinning processes for a wafer-level 3D interconnect technology platform

Abstract

A previously proposed wafer-level 3D IC technology platform has been extensively evaluated for compatibility with conventional IC packaging. Results demonstrate that the dielectric glue bonding using benzocyclobutene (BCB) is compatible with conventional wafer sawing techniques, and that the bond adhesion strength is unaffected by die-level autoclave and thermal shock testing. High-resolution X-ray diffraction (HRXRD) results show that the stress levels in 70 nm or 140 nm thick silicon SOI layers had no appreciable change after BCB bonding and wafer-thinning.