Title :
Transfer and non-transfer stacking technologies based on chip-to-wafer self-asembly for high-throughput and high-precision alignment and microbump bonding
Author :
Takafumi Fukushima;Taku Suzuki;Hideto Hashiguchi;Chisato Nagai;Jichoel Bea;Hiroyuki Hashimoto;Mariappan Murugesan;Kang-Wook Lee;Tetsu Tanaka;Kazushi Asami;Yasuhiro Kitamura;Mitsumasa Koyanagi
Author_Institution :
Department of Bioengineering and Robotics, Graduate School of Engineering, Tohoku University, 6-6-12 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan
Abstract :
Two types of high-throughput and high-precision multichip-to-wafer 3D stacking approaches are demonstrated: one is non-transfer stacking and the other one is transfer stacking. Both the stacking approaches employ a self-assembly technologies using liquid surface tension. In the former stacking scheme, large number of chips having 20-µm-square Cu/SnAg microbumps are directly self-assembled face-down on an interposer wafer, like flip-chip bonding. On the other hand, in the latter stacking scheme, the many chips having the microbumps are self-assembled face-up on a carrier wafer with bipolar electrodes for electrostatic chucking. Then, the latter chips are transferred from the carrier to another interposer in wafer-level processing. The alignment accuracies are evaluated and compared between the two stacking approaches. The resulting daisy chains show good electrical properties comparable to conventional flip-chip bonding.
Keywords :
"Self-assembly","Semiconductor device measurement","Throughput"
Conference_Titel :
3D Systems Integration Conference (3DIC), 2015 International
DOI :
10.1109/3DIC.2015.7334578