Title :
Novel 3-dimensional integration technique of chip-on-wafer (COW) for MEMS applications
Author :
Fujimoto, Kenji ; Yoshimi, S. ; Maeda, Noboru ; Kodama, Shinsuke ; Young Suk Kim ; Kitada, H. ; Mizushima, Y. ; Nakamura, T. ; Suzuki, Kenji ; Ohba, Tsuyoshi
Author_Institution :
Sch. of Eng., Univ. of Tokyo, Tokyo, Japan
Abstract :
The structure of chip-on-wafer (COW) employed off-chip interconnects was successfully fabricated and electrically connected between chips and a base wafer with bump-less contact. The chips were thinned down to 5μm and stacked on the base wafer with an adhesive layer. The space between the chips was filled by non-conductive polymer. The through via holes were formed on polymer by Reactive Ion Etching (RIE) and filled up with Copper using Electro-Chemical Deposition (ECD). Lower leakage current as low as back ground was found between the metal pads. No failure and an approximate 100% yield were achieved in the vertical wiring for multi-chips COW stacking.
Keywords :
copper; integrated circuit interconnections; leakage currents; micromechanical devices; sputter etching; stacking; 3D integration; ECD; MEMS; adhesive layer; base wafer; bumpless contact; chip-on-wafer; electrochemical deposition; leakage current; metal pads; multichips COW stacking; nonconductive polymer; off-chip interconnects; reactive ion etching; size 5 mum; through via holes; Bonding; Etching; Glass; Micromechanical devices; Polymers; Resistance; Sensors;
Conference_Titel :
Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP), 2013 Symposium on
Conference_Location :
Barcelona
Print_ISBN :
978-1-4673-4477-7
