Preparation of Longitudinally Oriented CoCrPt Thin Film in GMR Head at Room Temperature

The CoCrPt thin films with longitudinal orientation of easy axis have been prepared by magnetron sputtering on CrW underlayer at room temperature. The crystallographic relationship between the CoCrPt thin film and the underlayer was studied, and the dependence of CoCrPt structure and magnetic properties on the Pt content was investigated. The addtion of Pt element in the CoCrPt magnetic layer increases the lattice constant and longitudinal coercivity of the CoCrPt thin films. The intrinsic stress of the CoCrPt(8.5% Pt content) thin film is analyzed by using the micromagnetic method. It is found that the in-plane magneto-elastic effect with a residual compressive stress on the order of 1.14 Gpa tends to enlarge the longitudinal coercivity, and the increased coercivity due to the magneto-elastic anisotropy is about 245 Oe, indicating that the magnetostriction effects play an important role on the coercivity mechanisms.