TY - GEN
T1 - Characterization of nano-grained high aspect ratio through-wafer copper interconnect column
AU - Xu, Luhua
AU - Dixit, Pradeep
AU - Pang, John H. L.
AU - Miao, Jianmin
AU - Zhang, Xi
AU - Tu, King-Ning
AU - Preisser, Robert
PY - 2007
Y1 - 2007
N2 - Through-wafer interconnect is one of the key technologies for fabricating next-generation compact 3-D microelectronic devices. The microstructure and mechanical properties of high aspect ratio through-wafer electroplated copper interconnects are reported in this paper. Copper was deposited in very high aspect ratio (∼15) and narrow DRIE etched through-vias (15 μm) in silicon substrate by electrodeposition. With the presence of nano-scale grains and higher density of nano-twins, the copper columns were found to have significant higher hardness and tensile strength than that of conventional coarse-grained copper, while retaining an electrical conductivity comparable to that of pure copper. The grain structure of electroplated copper was found out by atomic force microscope and transmission electron microscope. The induced strain, a result of mismatch in coefficient of thermal expansion, was studied by digital image speckle correlation analysis, when the copper interconnects were subjected to a temperature cycle from 25°C to 125°C. © 2007 IEEE.
AB - Through-wafer interconnect is one of the key technologies for fabricating next-generation compact 3-D microelectronic devices. The microstructure and mechanical properties of high aspect ratio through-wafer electroplated copper interconnects are reported in this paper. Copper was deposited in very high aspect ratio (∼15) and narrow DRIE etched through-vias (15 μm) in silicon substrate by electrodeposition. With the presence of nano-scale grains and higher density of nano-twins, the copper columns were found to have significant higher hardness and tensile strength than that of conventional coarse-grained copper, while retaining an electrical conductivity comparable to that of pure copper. The grain structure of electroplated copper was found out by atomic force microscope and transmission electron microscope. The induced strain, a result of mismatch in coefficient of thermal expansion, was studied by digital image speckle correlation analysis, when the copper interconnects were subjected to a temperature cycle from 25°C to 125°C. © 2007 IEEE.
UR - https://www.scopus.com/pages/publications/35348915635
UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-35348915635&origin=recordpage
U2 - 10.1109/ECTC.2007.374078
DO - 10.1109/ECTC.2007.374078
M3 - RGC 32 - Refereed conference paper (with host publication)
SN - 1-4244-0984-5
T3 - Proceedings - Electronic Components and Technology Conference
SP - 2011
EP - 2016
BT - 2007 PROCEEDINGS - 57th Electronic Components & Technology Conference
PB - IEEE
T2 - 57th Electronic Components and Technology Conference (ECTC '07)
Y2 - 29 May 2007 through 1 June 2007
ER -