Structural and magnetic properties of micropolycrystalline cobalt thin films fabricated by direct current magnetron sputtering

Kerui Song; Zhou Li; Mei Fang; Zhu Xiao; Qian Lei

doi:10.1007/s12613-023-2715-5

Volume 31 Issue 2

Feb. 2024

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Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2024 > 31(2): 384-394

Kerui Song, Zhou Li, Mei Fang, Zhu Xiao, and Qian Lei, Structural and magnetic properties of micropolycrystalline cobalt thin films fabricated by direct current magnetron sputtering, Int. J. Miner. Metall. Mater., 31(2024), No. 2, pp. 384-394. https://doi.org/10.1007/s12613-023-2715-5

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Kerui Song, Zhou Li, Mei Fang, Zhu Xiao, and Qian Lei, Structural and magnetic properties of micropolycrystalline cobalt thin films fabricated by direct current magnetron sputtering, Int. J. Miner. Metall. Mater., 31(2024), No. 2, pp. 384-394. https://doi.org/10.1007/s12613-023-2715-5

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Research Article

Structural and magnetic properties of micropolycrystalline cobalt thin films fabricated by direct current magnetron sputtering

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Corresponding author:
Zhu Xiao E-mail: xiaozhumse@163.com
Received: 18 April 2023; Revised: 6 June 2023; Accepted: 26 July 2023; Available online: 27 July 2023

Abstract

Abstract

Pure cobalt (Co) thin films were fabricated by direct current magnetron sputtering, and the effects of sputtering power and pressure on the microstructure and electromagnetic properties of the films were investigated. As the sputtering power increases from 15 to 60 W, the Co thin films transition from an amorphous to a polycrystalline state, accompanied by an increase in the intercrystal pore width. Simultaneously, the resistivity decreases from 276 to 99 μΩ·cm, coercivity increases from 162 to 293 Oe, and in-plane magnetic anisotropy disappears. As the sputtering pressure decreases from 1.6 to 0.2 Pa, grain size significantly increases, resistivity significantly decreases, and the coercivity significantly increases (from 67 to 280 Oe), which can be attributed to the increase in defect width. Correspondingly, a quantitative model for the coercivity of Co thin films was formulated. The polycrystalline films sputtered under pressures of 0.2 and 0.4 Pa exhibit significant in-plane magnetic anisotropy, which is primarily attributable to increased microstress.
- cobalt thin film;
- magnetron sputtering;
- microstructure;
- electromagnetic properties

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