High-temperature compatible 3D-integration processes for a vacuum-sealed CNT-based NEMS

A System-in-Package (SiP) concept for the 3D-integration of a Single Wall Carbon Nanotube (SWCNT) resonator with its CMOS driving electronics is presented. The key element of this advanced SiP is the monolithic 3D-integration of the MEMS with the CMOS electronics using Through Silicon Vias (TSVs) on an SOI wafer. This SiP includes: • A glass cap vacuum-sealed to the main wafer using an eutectic bonding process: a low leak rate of 2.7 × 10 -9 mbar·l/s was obtained; • Platinum-TSVs, compatible with the SWCNT growth and release process; The TSVs were developed in a "via first" process and characterized at high-temperature - up to 850°C. An ohmic contact between the Pt-metallization and the SOI silicon device layer was obtained; • The driving CMOS electronic device is assembled to the MEMS using an Au stud bump technology. Keywords: System-in-Package (SiP), vacuum packaging, eutectic bonding, "via-first" TSVs, high-temperature platinum interconnects, ohmic contacts, Au-stud bumps assembly, CMOS electronics. © 2013 Copyright SPIE.