Unit processes for Cu/BCB redistribution layer bonding for 3D ICs
2006 (English)In: Advanced Metallization Conference 2005 (AMC 2005) / [ed] Brongersma SH; Taylor TC; Tsujimura M; Masu K, WARRENDALE: MATERIALS RESEARCH SOCIETY , 2006, 179-183 p.Conference paper (Refereed)
A novel via-first, back-end-of-the-line (BEOL) compatible, monolithic wafer-level three-dimensional (3D) interconnect technology platform is presented. This platform employs wafer bonding of damascene-patterned metal/adhesive redistribution layers on two wafers to provide both high density of inter-wafer electrical interconnects and strong adhesive bond of two wafers in a single unit processing step. Two key steps for this approach are 1) fabrication of a metal/adhesive redistribution layer on the BEOLprocessed wafers by damascene patterning and 2) face-to-face alignment and bonding of two wafers utilizing copper/tantalum (Cu/Ta) and benzocyclobutene (BCB) redistribution layers. A baseline process and two modified processes are investigated toward evaluation of 1) acceptable wafer-scale nonplanarity, removal rate, and surface damage after CMP and 2) seamless bonding at all three possible interfaces with sufficiently strong BCB-to-BCB critical adhesion energy and Cu-to-Cu contact resistance. Migration of voids in the sputtered copper during bonding and etch profiles for different etch processes are discussed.
Place, publisher, year, edition, pages
WARRENDALE: MATERIALS RESEARCH SOCIETY , 2006. 179-183 p.
IdentifiersURN: urn:nbn:se:kth:diva-24813ISI: 000236430900023ScopusID: 2-s2.0-33644939035ISBN: 1-55899-865-9OAI: oai:DiVA.org:kth-24813DiVA: diva2:353436
22nd Annual Advanced Metallization Conference (AMC) Colorado Springs, CO, SEP 27-29, 2005
QC 201009272010-09-272010-09-272010-09-27Bibliographically approved