# 전착법을 이용한 Co계 합금박막의 표면형태와 자기특성과의 관계

• Han, Chang-Suk (Department of ICT Automotive Engineering, Hoseo University) ;
• Kim, Sang-Wook (Department of Nanobiotronics, Hoseo University)
• 한창석 (호서대학교 자동차ICT공학과) ;
• 김상욱 (호서대학교 나노바이오트로닉스학과)
• Accepted : 2017.10.20
• Published : 2017.11.27

#### Abstract

In this study, we investigated the overpotential of precipitation related to the catalytic activity of electrodes on the initial process of electrodeposition of Co and Co-Ni alloys on polycrystalline Cu substrates. In the case of Co electrodeposition, the surface morphology and the magnetic property change depending on the film thickness, and the relationship with the electrode potential fluctuation was shown. Initially, the deposition potential(-170 mV) of the Cu electrode as a substrate was shown, the electrode potential($E_{dep}$) at the $T_{on}$ of electrodeposition and the deposition potential(-600 mV) of the surface of the electrodeposited Co film after $T_{off}$ and when the pulse current was completed were shown. No significant change in the electrode potential value was observed when the pulse current was energized. However, in a range of number of pulses up to 5, there was a small fluctuation in the values of $E_{dep}$ and $E_{imm}$. In addition, in the Co-Ni alloy electrodeposition, the deposition potential(-280 mV) of the Cu electrode as the substrate exhibited the deposition potential(-615 mV) of the electrodeposited Co-Ni alloy after pulsed current application, the $E_{dep}$ of electrodeposition at the $T_{on}$ of each pulse and the $E_{imm}$ at the $T_{off}$ varied greatly each time the pulse current was applied. From 20 % to less than 90 % of the Co content of the thin film was continuously changed, and the value was constant at a pulse number of 100 or more. In any case, it was found that the shape of the substrate had a great influence.

#### References

1. C. S. Han, C. H. Chun and S. O. Han, Korean J. Mater. Res., 19, 319 (2009). https://doi.org/10.3740/MRSK.2009.19.6.319
2. S. Wang, Y. He, J. Zou, Y. Jiang, J. Xu, B. Huang, C. T. Liu and P. K. Liaw, J. Crys. Grow., 306, 433 (2007). https://doi.org/10.1016/j.jcrysgro.2007.05.043
3. H. Tang, L. Zhu, Z. Ye, H. He, Y. Zhang, M. Zhi, F. Yang, Z. Yang and B. Zhao, Mater. Lett., 61, 1170 (2007). https://doi.org/10.1016/j.matlet.2006.06.085
4. J. Woltersdorf and E. Pippel, Thin Solid Films, 116, 77 (1984). https://doi.org/10.1016/0040-6090(84)90401-2
5. J. Schwarzkopf, M. Schmidbauer, A. Duk, A. Kwasniewski, S. B. Anooz, G. Wagner, A. Devi and R. Fornari, Thin Solid Films, 520, 239 (2011). https://doi.org/10.1016/j.tsf.2011.07.050
6. A. Molenaar and J. W. G. de Bakker, J. Electrochem. Soc., 136, 378 (1989). https://doi.org/10.1149/1.2096639
7. N. A. Pangarov and G. S. Sotirova, Galvanotechnik, 66, 821 (1975).
8. P. Cettou, P. M. Robertson, and N. Ibl, Electrochim. Acta, 29, 875 (1984). https://doi.org/10.1016/0013-4686(84)87131-5