Patent ID: 7828985
Filing Date: 2010-11-09
Classification: G11B

Abstract:
1. A method of producing a thin film magnetic head, comprising the steps of: forming a first lower magnetic pole layer; forming a second lower magnetic pole layer in a part on the first lower magnetic pole layer; forming a nonmagnetic insulating layer on the first and second lower magnetic pole layers, the nonmagnetic insulating layer being less etched than the second lower magnetic pole layer; removing a part of the nonmagnetic insulating layer until an entire upper surface of the second lower magnetic pole layer in a stacking direction is exposed; forming a concave portion, that has a bottom portion and a side wall portion, by etching the second lower magnetic pole layer and the nonmagnetic insulating layer until a thickness of the second lower magnetic pole layer is thinner than that of the nonmagnetic insulating layer, thereby the bottom portion of the concave portion is configured by the second lower magnetic pole layer, the side wall portion of the concave portion is configured by the nonmagnetic insulating layer and a width of the second lower magnetic pole layer in a track width direction corresponds to a distance of the nonmagnetic insulating layer in the track width direction, forming a recording gap layer so as to cover at least a surface of the second lower magnetic pole layer and not to cover a whole surface of the side wall portion; and forming a first upper magnetic pole layer, whose width in the track width direction corresponds to the width of the second lower magnetic pole layer in the track width direction on the recording gap layer in the concave portion so as to fill the concave portion.