Patent ID: 7609479
Filing Date: 2009-10-27
Classification: G11B

Abstract:
1. 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; and a shield, wherein: the shield incorporates: a first layer having an end face located in a region of the medium facing surface forward of the end face of the pole layer along a direction of travel of the recording medium; a second layer disposed in a region sandwiching the pole layer with the first layer; a first coupling portion coupling the first layer to the second layer without touching the pole layer; and a second coupling portion coupling the pole layer to the second layer and located farther from the medium facing surface than the first coupling portion; the magnetic head further comprises a gap layer made of a nonmagnetic material and disposed between the pole layer and the first layer; in the medium facing surface, the end face of the first layer is located at a specific distance created by a thickness of the gap layer from the end face of the pole layer; the end face of the pole layer has a side located adjacent to the gap layer, the side defining a track width; part of the coil passes through a space surrounded by the pole layer, the second layer, the first coupling portion and the second coupling portion; the first coupling portion couples the first layer to the second layer on both sides of the pole layer opposed to each other in a direction of track width, the first coupling portion incorporating: the first layer is coupled to the pole layer through the first coupling portion, the second layer and the second coupling portion only, wherein the first coupling portion, the second layer and the second coupling portion form only one magnetic path for passing a magnetic flux between the first layer and the pole layer.