Thin film magnetic head with electroplated Ni-Fe alloy thin film having small average crystal grain size range

摘要

A slider having a thin film magnetic head. The thin film magnetic head has an upper magnetic core, a lower magnetic core and a coil disposed between the upper magnetic core and the lower magnetic core. The upper magnetic core and the lower magnetic core is an electroplated thin film with an average crystal grain size smaller than 500 Å, and the electroplated thin film is made of Ni-Fe alloy of which Ni is 38 to 60 wt % and Fe is 40 to 62 wt %.