Anisotropic properties of oblique angle deposited permalloy thin films

The structural, transport, and magnetic properties of permalloy (Ni81Fe19) thin films prepared by oblique angle deposition have been investigated. With the increasing oblique angle, column-like microstructures developed on the films while their porosity augmented. Due to the unique columnar microstructures, a deposition-angledependent uniaxial anisotropy was induced in the films. While the normally deposited film was electrically isotropic, the films grown at non-zero angles showed enhanced anisotropic conduction. The magnetization data showed that for the films deposited at angles 70 degrees the easy magnetization axis was along the films in-plane direction and perpendicular to the incident flux direction. As the oblique angle exceeded 70 degrees the magnetization easy-axis reoriented along the long-columnar axis. The systematic increase of oblique angle triggered a noticeable enhancement in the coercivity , especially for the extreme oblique angles (alpha 70 degrees). The experimental results demonstrated that oblique angle deposition, particularly at angles > 70 degrees, can substantially transform the electro-magnetic properties of thin films.