Fe–Co–B/[Ni–Fe/Si] soft magnetic underlayer with high anisotropy field along cross-track direction on disk substrate

Effect of Low‐Frequency Alternative‐Current Magnetic Susceptibility in Ni80Fe20 Thin Films

“…Zawilski's theory provides a sounder theoretical basis for frequency of susceptibility application [7]. Some soft material experiments have been performed using Ni 80 Fe 20 or CoFeB film because it has a high saturation magnetization (M s ), low coercivity (H c ), and a highly anisotropic field (H k ) for use in magnetoresistance random access memory (MRAM) applications [8][9][10][11]. Some studies have discussed the benefits of alternative magnetic susceptibility measurement approaches, such as using a wide range of frequencies from 10 Hz to 25000 Hz in investigations of environmental magnetism even if to estimate the distribution of grain sizes of superparamagnetic particles and to determine the critical temperature (T c ) of ferromagnetic materials [12].…”

Improvement of in-plane anisotropy field in FeCoB/NiFe/Si thin films by Kr sputtering

“…FeCoB/NiFe/Si thin film is one of the hopeful candidates which possess the properties mentioned above. It shows large 4pM s of 22 kG and, moreover, quite high H k of several hundreds Oe which is over tenth of other conventional soft magnetic materials [2]. However, the high in-plane magnetic anisotropy field H k: appeared only in the specimens deposited on Si wafers.…”

Effect of thermal process on magnetic anisotropy in FeCoB soft underlayer

“…The thickness of these layers 2, 10, 200 nm, respectively. Si/NiFe layers were prepared for controlling surface energy and enhancing magnetic anisotropy in the FeCoB layer [2]. The films for study of substrate heating were sputtered at Ar gas pressure of 1 mTorr.…”

“…We reported in the previous paper that the FeCoB thin films fabricated by using facing targets sputtering showed high H k up to 380 Oe. [2] An FeCoB film also showed high saturation magnetization 4p M s of 22 kG and low H c of 10 Oe; therefore, these films might well be an expected candidate for SULs.…”