Writing characteristics of pole-trimmed MR heads comprising composite shared poles

A 3-dimensional model was developed to better understand the characteristics of pole-trimmed MR write heads using finite element method. Quantitative analyses of recording heads as a function of shared pole structure, gap length and magnetic spacing, and their effects on the recording performance such as overwrite and transition parameter have been studied. In this study, heads with composite shared pole structure (with high Bs top layer) show larger gap field, more symmetric field pattern, smaller transition length, and enhanced overwrite.