Effect of polycrystalline sublayer films on the magnetic and structural properties of CoCr films

The magnetic and structural properties of Co-18 at. % Cr films were evaluated for high density longitudinal recording applications. The films exhibited in-plane magnetization, high coercivity (≲1000 Oe), and hysteresis loop squareness of 0.7-0.89 when the CoCr films were sputtered on sublayer films of Cr or Cr-20 at. % Co. The coercivity was correlated with the thicknesses of the CoCr film and the sublayer, the deposition conditions, and the percentage of CoCr grains with c-axis preferred orientation in the film plane.