Method for shaping pole pieces of magnetic heads by chemical mechanical polishing

摘要

A thin film magnetic head that includes an improved P 2 pole tip/yoke interface. The process for forming the P 2 pole tip/yoke interface includes a CMP polishing step that is performed on the surface of the wafer subsequent to the plating of the P 2 pole tip. This CMP step utilizes a relatively soft polishing pad and an acidic polishing slurry which preferentially attacks the P 2 pole tip material, such that the CMP step results in the recession of the upper surface of the P 2 pole tip relative to the dielectric layer surrounding it, as well as the significant rounding of the upper edges of the dielectric trench in which the P 2 pole tip is formed. Thereafter, when the yoke is plated onto the P 2 pole tip the rounded upper edges of the dielectric trench result in a concave curved interface between the yoke and the P 2 pole tip.