{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T13:23:20Z","timestamp":1768742600365,"version":"3.49.0"},"reference-count":46,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2016,10,10]],"date-time":"2016-10-10T00:00:00Z","timestamp":1476057600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>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).<\/jats:p>","DOI":"10.3390\/mi7100184","type":"journal-article","created":{"date-parts":[[2016,10,10]],"date-time":"2016-10-10T10:35:19Z","timestamp":1476095719000},"page":"184","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Oxide-Oxide Thermocompression Direct Bonding Technologies with Capillary Self-Assembly for Multichip-to-Wafer Heterogeneous 3D System Integration"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2303-8178","authenticated-orcid":false,"given":"Takafumi","family":"Fukushima","sequence":"first","affiliation":[{"name":"Department of Mechanical Systems Engineering, Graduate School of Engineering, Tohoku University, 6-6-12 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Miyagi, Japan"},{"name":"New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan"}]},{"given":"Hideto","family":"Hashiguchi","sequence":"additional","affiliation":[{"name":"Department of Mechanical Systems Engineering, Graduate School of Engineering, Tohoku University, 6-6-12 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Miyagi, Japan"}]},{"given":"Hiroshi","family":"Yonekura","sequence":"additional","affiliation":[{"name":"New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan"},{"name":"Tohoku-MicroTec Co., Ltd., 6-6-12 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan"}]},{"given":"Hisashi","family":"Kino","sequence":"additional","affiliation":[{"name":"Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai 980-8579, Miyagi, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3510-7110","authenticated-orcid":false,"given":"Mariappan","family":"Murugesan","sequence":"additional","affiliation":[{"name":"New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan"}]},{"given":"Ji-Chel","family":"Bea","sequence":"additional","affiliation":[{"name":"New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan"}]},{"given":"Kang-Wook","family":"Lee","sequence":"additional","affiliation":[{"name":"New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan"}]},{"given":"Tetsu","family":"Tanaka","sequence":"additional","affiliation":[{"name":"Department of Mechanical Systems Engineering, Graduate School of Engineering, Tohoku University, 6-6-12 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Miyagi, Japan"},{"name":"Department of Biomedical Engineering, Graduate School of Biomedical Engineering, Tohoku University, Sendai 980-8579, Miyagi, Japan"}]},{"given":"Mitsumasa","family":"Koyanagi","sequence":"additional","affiliation":[{"name":"New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579, Miyagi, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2016,10,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1557\/mrs.2015.32","article-title":"Three-dimensional integration: An industry perspective","volume":"40","author":"Iyer","year":"2015","journal-title":"MRS Bull."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Matsumoto, T., Kudoh, Y., Tahara, M., Yu, K.-H., Miyakawa, N., Itani, H., Ichikizaki, T., Fujiwara, A., Tsukamoto, H., and Koyanagi, M. 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