Patent ID: 7554766

Claim:
A magnetic head for perpendicular magnetic recording comprising: a medium facing surface that faces toward a recording medium; a coil for generating a magnetic field corresponding to data to be written on the recording medium; a pole layer having an end face located in the medium facing surface, allowing a magnetic flux corresponding to the field generated by the coil to pass therethrough, and generating a write magnetic field for writing the data on the recording medium by means of a perpendicular magnetic recording system; shield layer having an end face located in the medium facing surface and having a portion that is located away from the medium facing surface and coupled to the pole layer; and a gap layer made of a nonmagnetic material and provided between the pole layer and the shield layer, wherein: in the medium facing surface, the end face of the shield layer is located forward of the end face of the pole layer along a direction of travel of the recording medium with a specific space; the pole layer incorporates: a track width defining portion that has a first end located in the medium facing surface and a second end opposite to the first end, and that defines the track width; and a wide portion coupled to the second end of the track width defining portion and having a width greater than a width of the track width defining portion; the pole layer further has: a top surface facing toward the shield layer with the gap layer disposed in between; a first portion including the end face of the pole layer located in the medium facing surface; and a second portion located farther from the medium facing surface than the first portion, the top surface of the pole layer being bent such that the second portion has a thickness greater than a thickness of the first portion; the shield layer further has a bottom surface facing toward the pole layer with the gap layer disposed in between; the gap layer and the bottom surface of the shield layer are bent to correspond to a shape of the top surface of the pole layer; and a value of NH×TH/WG is greater than zero and smaller than or equal to 0.85 μm, where NH is a distance from the medium facing surface to a boundary between the track width defining portion and the wide portion, TH is a distance from the medium facing surface to a point at which a space between the pole layer and the shield layer starts to be greater than a space between the pole layer and the shield layer taken in the medium facing surface, and WG is the space between the pole layer and the shield layer taken in the medium facing surface.