Effect of Pd Buffer and Interlayer on the Magnetic Properties of CoCrPt-Oxide Granular Thin Films

• Published in: IEEE transactions on magnetics 2018-08, Vol.54 (8), p.1-5
• Main Authors: Tsai, Jai Lin, Pi, Chen, Chang, Yuan Shuo, Wu, Yu Ting, Chen, Yu Ren, Chang, Ching Wei, Varvaro, Gaspare
• Format: Article
• Language: English
• Subjects: Amorphous magnetic materials; Buffer layers; Coercivity; Crystallography; Interlayers; Intermediate layer; lattice distortion; Magnetic anisotropy; Magnetic properties; Magnetism; Magnetometers; Perpendicular magnetic anisotropy; Perpendicular magnetic recording; Thin films; Titanium dioxide
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2018.2837023

Morphostructural and magnetic properties of CoCrPt-oxide (TiO 2 , CoO) granular thin films deposited on Pd( y )/Ru/Pd( x )/NiTa intermediate layer have been investigated as a function of the Pd thickness ( x = 5 and 10 nm; y = 1, 3 , and 5 nm). The Pd( x ) buffer layer shows an fcc (111) texture that leads to a gradual improvement of both the Ru and CoCrPt hcp (0002) crystallographic orientations while increasing the Pd thickness. This results on a significant enhancement of both the effective magnetic anisotropy ( {K} _{\mathrm {eff}} =4.1 \times 10^{6} erg/cm 3 ) and out-of-plane coercivity ( {H} _{c\bot } = 5.7 kOe) with respect to the reference CoCrPt-oxides/Ru/NiTa sample ( K_{\mathrm {eff}} = 3.4 \times 10^{6} erg/cm 3 , {H} _{c\bot }= 4.7 kOe) when a 10 nm-thick Pd buffer is used. The inclusion of a Pd( y ) intermediate layer between Ru and Co leads to an increase of the effective anisotropy (up to 4.1 \times 10^{6} erg/cm 3 for y = 5 nm) with respect to the reference sample, which can be ascribed to a combined effect of an interface contribution and a term arising from a CoCrPt lattice distortion.