During MEMS pressure sealing by SLID junction of Cu-Sn, in process of bonding, local bulges appear in molten Sn layer and hinder the formation of vacuum-tight SLID coupling of Cu-Sn. In this work, using means of video recording the cause of bulges formation by hydrostatic surface tension forces in melted Sn has been identified. The interrelation of bulges presence with changes in regime of Sn diffusion to Cu matrix and ensuring vacuum tightness of SLID coupling is shown. It was experimentally confirmed that the most stable regime of Sn diffusion to Cu matrix and the formation of vacuum-tight SLID coupling during bonding are provided by Sn layer having a thickness lesser than critical Laplace radius.
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Key words:
bonding, SLID, surface tension, Wafer Level Packaging
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Published in:
Technological processes and routes
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Bibliography link:
Grabov A. B., Riskin D. D., Suzdaltsev S. Yu., Obizhaev D. Yu., Zhukova S. A. Study on the role of hydrostatic effects in molten Sn layer in the formation of a vacuum-tight SLID coupling of Cu-Sn. Proc. Univ. Electronics, 2024, vol. 29, no. 2, pp. 168–174. https://doi.org/10.24151/1561-5405-2024-29-2-168-174
Alexey B. Grabov
Central Research Institute of Chemistry and Mechanics (Russia, 115487, Moscow, Nagatinskaya st., 16A)
Dmitry D. Riskin
Central Research Institute of Chemistry and Mechanics (Russia, 115487, Moscow, Nagatinskaya st., 16A)
Sergey Yu. Suzdaltsev
Central Research Institute of Chemistry and Mechanics (Russia, 115487, Moscow, Nagatinskaya st., 16A)
Denis Yu. Obizhaev
Central Research Institute of Chemistry and Mechanics (Russia, 115487, Moscow, Nagatinskaya st., 16A)
Svetlana A. Zhukova
Central Research Institute of Chemistry and Mechanics (Russia, 115487, Moscow, Nagatinskaya st., 16A)
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