Abstract
The magnetic anisotropy in Ni films deposited by ion beam sputtering (IBS), triode rf sputtering and diode rf sputtering, was studied in relation to the internal stress in the films. Strong in-plane easy magnetic anisotropy (Ku∼-5 ×105 erg/cm3) was observed in IBS Ni films deposited at an acceleration voltage above 1 kV at room temperature. The internal compressive stress was found to be as large as -1.2×1010 dyn/cm2, which causes a stress-induced magnetic anisotropy of about -1.2×106 erg/cm3 in the IBS Ni films. There is some positive contribution to the magnetic anisotropy, possibly due to anisotropic internal shape effect (Kint∼6 ×105 erg/cm3). Both this perpendicular magnetic anisotropy and the stress-induced in-plane anisotropy are reduced with increasing substrate temperature during deposition. It is possible to obtain a stress-free isotropic IBS Ni film at an appropriate substrate temperature (250∼300°C) and an acceleration voltage (1.1 kV) of the ion beam
