Obliquely sputtered Co/Cr thin film tape for bidirectional recording

We report the growth and properties of a thin film tape, which can be equivalently recorded in both directions. The experimental tape consists of a 20 nm thick Co layer grown on top of a Cr underlayer 120 nm. The two layers were consecutively sputtered at incident angle of 70° at room temperature onto a rotating drum covered with a polymer substrate. In such growth geometry the running direction of drum is perpendicular to the incidence plane of arriving atoms. As a result of this configuration, a medium with a good orientation of the easy axis along the recording direction as well as a high coercivity of 180 kA/m has been prepared. Recording measurements have been carried out and illustrate the bidirectional recording behavior of this experimental tape, which seems to be very promising for high-density tape recording.