Oxide-Oxide Thermocompression Direct Bonding Technologies with Capillary Self-Assembly for Multichip-to-Wafer Heterogeneous 3D System Integration
Takafumi Fukushima,
Hideto Hashiguchi,
Hiroshi Yonekura,
Hisashi Kino,
Mariappan Murugesan,
Ji-Chel Bea,
Kang-Wook Lee,
Tetsu Tanaka,
Mitsumasa Koyanagi
Affiliations
Takafumi Fukushima
Department of Mechanical Systems Engineering, Graduate School of Engineering, Tohoku University, 6-6-12 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Miyagi, Japan
Hideto Hashiguchi
Department of Mechanical Systems Engineering, Graduate School of Engineering, Tohoku University, 6-6-12 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Miyagi, Japan
Hiroshi Yonekura
New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan
Hisashi Kino
Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai 980-8579, Miyagi, Japan
Mariappan Murugesan
New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan
Ji-Chel Bea
New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan
Kang-Wook Lee
New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan
Tetsu Tanaka
Department of Mechanical Systems Engineering, Graduate School of Engineering, Tohoku University, 6-6-12 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Miyagi, Japan
Mitsumasa Koyanagi
New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan
Plasma- and water-assisted oxide-oxide thermocompression direct bonding for a self-assembly based multichip-to-wafer (MCtW) 3D integration approach was demonstrated. The bonding yields and bonding strengths of the self-assembled chips obtained by the MCtW direct bonding technology were evaluated. In this study, chemical mechanical polish (CMP)-treated oxide formed by plasma-enhanced chemical vapor deposition (PE-CVD) as a MCtW bonding interface was mainly employed, and in addition, wafer-to-wafer thermocompression direct bonding was also used for comparison. N2 or Ar plasmas were utilized for the surface activation. After plasma activation and the subsequent supplying of water as a self-assembly mediate, the chips with the PE-CVD oxide layer were driven by the liquid surface tension and precisely aligned on the host wafers, and subsequently, they were tightly bonded to the wafers through the MCtW oxide-oxide direct bonding technology. Finally, a mechanism of oxide-oxide direct bonding to support the previous models was discussed using an atmospheric pressure ionization mass spectrometer (APIMS).
