Pulse Electroplating of Nanotwinned Copper Using MPS-PEG Two-Additive System for Damascene via Filling Process

Authors

Yu-Xi Wang, Shenzhen Institute of Advanced Electronic Materials, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; Nano Science and Technology Institute, University of Science and Technology of China, Suzhou 215213, China
Li-Yin Gao, Shenzhen Institute of Advanced Electronic Materials, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, ChinaFollow
Yong-Qiang Wan, Shenzhen Institute of Advanced Electronic Materials, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
Zhe Li, Shenzhen Institute of Advanced Electronic Materials, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
Zhi-Quan Liu, Shenzhen Institute of Advanced Electronic Materials, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; Nano Science and Technology Institute, University of Science and Technology of China, Suzhou 215213, ChinaFollow

Corresponding Author

Li-Yin Gao(ly.gao@siat.ac.cn);
Zhi-Quan Liu (zqliu@siat.ac.cn)

Abstract

High density nanotwinned copper films were pulse electroplated using an optimized electrolyte. In order to find out the influencing factors on the formation of nanotwins, series contents of MPS were added to the electrolyte during the pulse electroplating process. It was found that the copper films electroplated without MPS had large grains but a few nanotwins. And the grain size was about 0.9 μm on average, and the texture components of (110) and (111) crystal orientations were calculated as 49% and 27.8%, respectively. Differently, when 10 ppm MPS was added, the microstructure was changed to columnar grain with high density of horizontal nanotwins and the crystal orientation was also changed to highly (111) orientated one. However, when the MPS content was continuously increased from 10 ppm to 40 ppm, the microstructure and crystal orientation were almost unchanged as detected by the secondary ion microscopy of focus ion beam and X ray diffraction. Specifically, when 40 ppm MPS was used, the average grain size was 0.6 μm, and the texture components of (110) and (111) crystal orientations were 3.45% and 95.1%, respectively. It demonstrated that the nanotwinned copper can be electroplated at a large concentration range of MPS, which also meant that the filling ability of nanotwinned copper electrolyte could be adjusted by MPS content without influencing the microstructure. Finally, these electrolytes with different contents of MPS were used in the Damascene via filling. The results showed that when the content of MPS was 40 ppm, the Damascus via was completely filled without voids. The achievement of via filling with nanotwinned copper makes the application of nanotwinned copper possible in Integrated Circuit (IC) fabrication, which also greatly promotes the development of interconnected material for next generation.

Graphical Abstract

Keywords

pulse electroplating; nanotwinned copper; via filling; Damascene process

DOI Link

https://doi.org/10.13208/j.electrochem.2209231

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Publication Date

2023-08-28

Online Available Date

2022-12-08

Revised Date

2022-11-23

Received Date

2022-09-23

Recommended Citation

Yu-Xi Wang, Li-Yin Gao, Yong-Qiang Wan, Zhe Li, Zhi-Quan Liu. Pulse Electroplating of Nanotwinned Copper Using MPS-PEG Two-Additive System for Damascene via Filling Process[J]. Journal of Electrochemistry, 2023 , 29(8): 2209231.
DOI: 10.13208/j.electrochem.2209231
Available at: https://jelectrochem.xmu.edu.cn/journal/vol29/iss8/3