Abstract: An upper auxiliary magnetic pole is formed in a space on a lower magnetic pole layer. A first insulating layer is then formed over the surface of the lower magnetic pole layer. The upper auxiliary magnetic pole is embedded within a swell formed on the surface of the first insulating layer. A second insulating layer is then formed over the surface of the first insulating layer. The second insulating layer has a property less abrasive than the first insulating layer. The second insulating layer is subjected to grinding over a wider area just after the swell has completely been removed. The abrasion can be suppressed at the thin film magnetic head in which the swell has been removed. The first insulating layer of a predetermined thickness reliably remains in each of the thin film magnetic heads on the wafer. An accurate adjustment of the thickness of the first insulating layer leads to a reliable establishment of a predetermined thickness in the upper auxiliary magnetic pole with less error.

Abstract: A liquid resist is introduced between adjacent conductive lines of a coil pattern girdling around a magnetic core piece. When the liquid resist is cured, an insulating resin filler can be fixed between the adjacent conductive lines of the coil pattern. An insulating metallic layer is formed to extend over the insulting resin filler and the conductive lines of the coil pattern. Thereafter, the insulating metallic layer is subjected to a flattening grinding treatment until at least a part of the conductive line is exposed at a flattened surface. Since the liquid of the resist, of a higher fluidity, penetrates in every hole and corner between the adjacent conductive lines, the gap defined between the adjacent conductive lines is fully filled with the insulating material. No voids remain in the gap. The conductive line of the coil can be reliably prevented from corrosion or oxidation.

Abstract: A liquid resist is introduced between adjacent conductive lines of a coil pattern girdling around a magnetic core piece. When the liquid resist is cured, an insulating resin filler can be fixed between the adjacent conductive lines of the coil pattern. An insulating metallic layer is formed to extend over the insulting resin filler and the conductive lines of the coil pattern. Thereafter, the insulating metallic layer is subjected to a flattening grinding treatment until at least a part of the conductive line is exposed at a flattened surface. Since the liquid of the resist, of a higher fluidity, penetrates in every hole and corner between the adjacent conductive lines, the gap defined between the adjacent conductive lines is fully filled with the insulating material. No voids remain in the gap. The conductive line of the coil can be reliably prevented from corrosion or oxidation.

Abstract: A thin film magnetic head includes an upper magnetic pole maintaining a constant thickness in a range determined by the so-called gap depth. A thinner film portion is defined in the upper magnetic pole in a range rearward of the range determined by the gap depth. The thinner film portion has a reduced thickness smaller than the constant thickness. The upper magnetic pole starts to enlarge the core width in the lateral direction at the rear end of the region determined by the so-called neck height. The neck height smaller than the gap depth serves to establish a reduction in the thickness of the upper magnetic pole after the upper magnetic pole gets larger in the lateral direction. A magnetic saturation can reliably be prevented at the thinner film portion in the upper magnetic pole. The front end of the upper magnetic pole is allowed to receive a larger quantity of a magnetic flux. It is possible to reliably enhance a magnetic field for recordation in the thin film magnetic head.

Abstract: An upper auxiliary magnetic pole is formed in a space on a lower magnetic pole layer. A first insulating layer is then formed over the surface of the lower magnetic pole layer. The upper auxiliary magnetic pole is embedded within a swell formed on the surface of the first insulating layer. A second insulating layer is then formed over the surface of the first insulating layer. The second insulating layer has a property less abrasive than the first insulating layer. The second insulating layer is subjected to grinding over a wider area just after the swell has completely been removed. The abrasion can be suppressed at the thin film magnetic head in which the swell has been removed. The first insulating layer of a predetermined thickness reliably remains in each of the thin film magnetic heads on the wafer. An accurate adjustment of the thickness of the first insulating layer leads to a reliable establishment of a predetermined thickness in the upper auxiliary magnetic pole with less error.