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Increasing passivation and reducing the Acknowledgements M. Gruffat, N. Launay, N. Arnal,
fluorine-free radical concentration helps This work was supported by the Science P. Godinat, “Fabrication of 3D
in the reduction of ER of the oxide at the and Engineering Research Council of packaging TSV using DRIE,” 2008
top corner. However, because of lower A*STAR (Agency for Science, Technology Symp. on Design, Test, Integration
passivation at the bottom of the TSV, the and Research), Singapore, under Grant No. and Packaging of MEMS/MOEMS,
oxide is continuously sputtered to the 12101E0008. Portions of this article were Nice, France, 2008, pp. 109-114, doi:
sidewalls and results in a higher ER. originally presented at the 2022 IEEE 10.1109/DTIP.2008.4752963.
To understand the optimized process 24th Electronics Packaging Technology 8. V. M. Don nelly, “Reactions
window for the DOE, JMP software is Conference (EPTC) and has been edited of fluorine atoms with silicon,
used to generate the predictive profile for publication in Chip Scale Review. revisited, again,” Jour. of Vacuum
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Biographies
Bhesetti S. S. Chandra Rao is a Senior Scientist at the Institute of Microelectronics, Agency for Science,
Technology and Research (A*STAR), Singapore. His research interests are 3D-IC, C2W and W2W bonding and
dry etch process technologies. He received a PhD from the NUS Singapore, a Master’s degree from the IISc,
Bangalore, and a Bachelors degree from the NIT, Warangal, India. Prior to this, he worked for 9 years at Lam
Research and Applied Materials in dry etch technology. He has served EPTC2021 as a Technical Chair and
General Chair for IEEE-EPTC 2022. Email Bhesetti_Chandra_Rao@ime.a-star.edu.sg

Hemanth Kumar Cheemalamarri is a Scientist at the Institute of Microelectronics, Agency for Science, Technology and
Research (A*STAR), Singapore. He completed his PhD from IIT Hyderabad, India, 2021. He is currently working as a research
scientist in W2W bonding technology for heterogeneous integration and MEMS applications.

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