High-performance CoPtCrO perpendicular media: optimizing exchange coupling and anisotropy orientation dispersion

A systematic investigation of the structural, magnetic, and recording properties of CoPtCrO media with different intergranular exchange coupling and anisotropy orientation dispersion is performed. Reduced exchange coupling between grains results in lower media transition jitter and nonlinear transition shift. By narrowing the Co anisotropy orientation dispersion, a substantial reduction of both transition and DC noise is achieved. Media with high squareness, coercivity, nucleation field, low exchange and narrow Co c-axis dispersion have been fabricated. Such media exhibit excellent recording performance and are promising for high-density perpendicular recording.