The (Anomalous) Hall Magnetometer as an Analysis Tool for High Density Recording Media

In this work an evaluation tool for the characterization of high-density recording thin film media is discussed. The measurement principles are based on the anomalous and the planar Hall effect. We used these Hall effects to characterize ferromagnetic Co-Cr films and Co/Pd multilayers having perpendicular anisotropy. The measurements set-up that was built has a sensitivity capable of measuring the hysteresis loops of 0.2x0.2 mm2 Hall structures in Co-Cr and jumps were observed in the Hall voltage as a function of the applied field. Easy-axis measurements have been carried out, but the results are not in complete agreement with conventional techniques. A thickness series of Co/Pd multilayers has been characterized with the planar Hall effect and the magnetoresistance ratio