Abstract
The effects of Co layer thickness and annealing temperature on the perpendicular magnetic anisotropy (PMA) properties of inverted [Pt (0.2 nm)/Co (tCo)]6 multilayers (where tCo indicates the thickness of the Co layer) have been investigated. The cross-sectional microstructure, as observed from the high-resolution transmission electron microscope images, shows a clear layered structure with atomically flat interfaces both in the as-deposited state as well as after annealing, indicating the interface effects for PMA. The effective PMA energy density (K eff) increases significantly with an increase in tCo from 0.2 to 0.28 nm and then becomes almost saturated with further increases in tCo, followed by a slight reduction at the highest Co thickness, tCo = 0.6 nm. In order to explain the tCo dependence on Keff, the intrinsic PMA energy density (Ki) is calculated by additionally measuring a similar set of results for the saturation magnetization. The Ki value increases nearly linearly with the increase in tCo from 0.2 to 0.5 nm, followed by saturation at a higher tCo value of 0.6 nm. Owing to a close relationship between Ki and the quality of the interfaces, these results indicate a similar tCo dependence on the quality of the interfaces. This is further supported from the magnetic measurements of the samples annealed at the highest temperature of 500 °C, where a second phase is formed, which show a similar tCo dependence on the amount of the second phase. The K i value is nearly independent of the annealing temperature at t Co ≤ 0.4 nm, above which a substantial reduction is observed, when the annealing temperature exceeds 500 °C.
| Original language | English |
|---|---|
| Article number | 173909 |
| Journal | Journal of Applied Physics |
| Volume | 114 |
| Issue number | 17 |
| DOIs | |
| Publication status | Published - 2013 Nov 7 |
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ASJC Scopus subject areas
- Physics and Astronomy(all)
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Effects of Co layer thickness and annealing temperature on the magnetic properties of inverted [Pt/Co] multilayers. / Lee, Tae Young; Won, Young Chan; Son, Dong Su; Lim, Sang Ho; Lee, Seong Rae.
In: Journal of Applied Physics, Vol. 114, No. 17, 173909, 07.11.2013.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Effects of Co layer thickness and annealing temperature on the magnetic properties of inverted [Pt/Co] multilayers
AU - Lee, Tae Young
AU - Won, Young Chan
AU - Son, Dong Su
AU - Lim, Sang Ho
AU - Lee, Seong Rae
PY - 2013/11/7
Y1 - 2013/11/7
N2 - The effects of Co layer thickness and annealing temperature on the perpendicular magnetic anisotropy (PMA) properties of inverted [Pt (0.2 nm)/Co (tCo)]6 multilayers (where tCo indicates the thickness of the Co layer) have been investigated. The cross-sectional microstructure, as observed from the high-resolution transmission electron microscope images, shows a clear layered structure with atomically flat interfaces both in the as-deposited state as well as after annealing, indicating the interface effects for PMA. The effective PMA energy density (K eff) increases significantly with an increase in tCo from 0.2 to 0.28 nm and then becomes almost saturated with further increases in tCo, followed by a slight reduction at the highest Co thickness, tCo = 0.6 nm. In order to explain the tCo dependence on Keff, the intrinsic PMA energy density (Ki) is calculated by additionally measuring a similar set of results for the saturation magnetization. The Ki value increases nearly linearly with the increase in tCo from 0.2 to 0.5 nm, followed by saturation at a higher tCo value of 0.6 nm. Owing to a close relationship between Ki and the quality of the interfaces, these results indicate a similar tCo dependence on the quality of the interfaces. This is further supported from the magnetic measurements of the samples annealed at the highest temperature of 500 °C, where a second phase is formed, which show a similar tCo dependence on the amount of the second phase. The K i value is nearly independent of the annealing temperature at t Co ≤ 0.4 nm, above which a substantial reduction is observed, when the annealing temperature exceeds 500 °C.
AB - The effects of Co layer thickness and annealing temperature on the perpendicular magnetic anisotropy (PMA) properties of inverted [Pt (0.2 nm)/Co (tCo)]6 multilayers (where tCo indicates the thickness of the Co layer) have been investigated. The cross-sectional microstructure, as observed from the high-resolution transmission electron microscope images, shows a clear layered structure with atomically flat interfaces both in the as-deposited state as well as after annealing, indicating the interface effects for PMA. The effective PMA energy density (K eff) increases significantly with an increase in tCo from 0.2 to 0.28 nm and then becomes almost saturated with further increases in tCo, followed by a slight reduction at the highest Co thickness, tCo = 0.6 nm. In order to explain the tCo dependence on Keff, the intrinsic PMA energy density (Ki) is calculated by additionally measuring a similar set of results for the saturation magnetization. The Ki value increases nearly linearly with the increase in tCo from 0.2 to 0.5 nm, followed by saturation at a higher tCo value of 0.6 nm. Owing to a close relationship between Ki and the quality of the interfaces, these results indicate a similar tCo dependence on the quality of the interfaces. This is further supported from the magnetic measurements of the samples annealed at the highest temperature of 500 °C, where a second phase is formed, which show a similar tCo dependence on the amount of the second phase. The K i value is nearly independent of the annealing temperature at t Co ≤ 0.4 nm, above which a substantial reduction is observed, when the annealing temperature exceeds 500 °C.
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U2 - 10.1063/1.4829024
DO - 10.1063/1.4829024
M3 - Article
AN - SCOPUS:84888396878
VL - 114
JO - Journal of Applied Physics
JF - Journal of Applied Physics
SN - 0021-8979
IS - 17
M1 - 173909
ER -