Electrochemical Deposition of Copper Pillar Bumps with High Uniformity

Authors

Bai-Zhao Tan, 1. School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006, P.R. China;
Jian-Lun Liang, 1. School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006, P.R. China;2. Jihua Laboratory, Foshan, Guangdong 528200, P.R. China;
Zi-Liang Lai, 1. School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006, P.R. China;
Ji-Ye Luo, 1. School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006, P.R. China;Follow

Corresponding Author

Ji-Ye Luo(luojiye@gdut.edu.cn)

Abstract

Electrochemical deposition of copper pillar bumps (CPBs) is one of the key technologies for the advanced packaging. In this study, the effects of the additive concentration, the electrolyte convection, the current density, and the electroplating system on the uniformity of the CPBs have been systematically investigated. The results showed that the profiles of the CPBs were mainly determined by the additive concentration, the bath convection and the current density, while the heights of the CPBs were mainly affected by the electroplating system. For the CPBs profiles, it was found that the low leveler concentration and high current density would generally result in domed shape, while the uneven agitation would lead to inclined surface. For the heights of CPBs, the macroscopic uniformity could be dramatically improved by a sophisticatedly designed electroplating system. These results can provide basic guidance for the optimization of the CPBs electroplating.

Graphical Abstract

Keywords

copper pillar bump, electrochemical deposition, uniformity, additive, leveler

DOI Link

https://doi.org/10.13208/j.electrochem.2213004

Publication Date

2022-07-28

Online Available Date

2022-04-19

Revised Date

2022-04-18

Received Date

2022-03-01

Recommended Citation

Bai-Zhao Tan, Jian-Lun Liang, Zi-Liang Lai, Ji-Ye Luo. Electrochemical Deposition of Copper Pillar Bumps with High Uniformity[J]. Journal of Electrochemistry, 2022 , 28(7): 2213004.
DOI: 10.13208/j.electrochem.2213004
Available at: https://jelectrochem.xmu.edu.cn/journal/vol28/iss7/7

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