Patent ID: 8295008
Filing Date: 2012-10-23
Classification: G11B

Abstract:
1. A magnetic head for perpendicular magnetic recording, comprising: a medium facing surface that faces a recording medium; a coil that produces a magnetic field corresponding to data to be written on the recording medium; a main pole that has an end face located in the medium facing surface, the main pole allowing a magnetic flux corresponding to the magnetic field produced by the coil to pass, and producing a write magnetic field for writing the data on the recording medium by means of a perpendicular magnetic recording system; a write shield made of a magnetic material; a gap part made of a nonmagnetic material and provided between the main pole and the write shield; and a substrate having a top surface, wherein: the coil, the main pole, the write shield, and the gap part are located above the top surface of the substrate; the write shield includes first and second side shields, and a top shield that is in contact with the first and second side shields; the first and second side shields have two end faces that are located in the medium facing surface at positions on opposite sides of the end face of the main pole in a track width direction; the top shield has an end face that is located in the medium facing surface at a position forward of the end face of the main pole along a direction of travel of the recording medium; the main pole has a first side part and a second side part that are opposed to each other in the track width direction; the first side shield has a first sidewall that faces the first side part of the main pole; the second side shield has a second sidewall that faces the second side part of the main pole; the gap part includes a gap film that is disposed to be in contact with the first and second sidewalls, and a nonmagnetic layer that is located away from the medium facing surface and interposed between the gap film and the first and second side parts; the first side part has a first side surface located in a first region and a third side surface located in a second region other than the first region, the first region extending from the medium facing surface to a position at a predetermined distance from the medium facing surface; the second side part has a second side surface located in the first region and a fourth side surface located in the second region; the nonmagnetic layer is not present between the first side surface and the first sidewall or between the second side surface and the second sidewall, but is present between the third side surface and the first sidewall and between the fourth side surface and the second sidewall; a distance between the third side surface and the first sidewall in the track width direction is greater than a distance between the first side surface and the first sidewall in the track width direction; a distance between the fourth side surface and the second sidewall in the track width direction is greater than a distance between the second side surface and the second sidewall in the track width direction; a distance between the first side surface and the second side surface in the track width direction decreases with increasing proximity to the top surface of the substrate; and angles that are formed by the third and fourth side surfaces with respect to a direction perpendicular to the top surface of the substrate are smaller than angles that are formed by the first and second side surfaces with respect to the direction perpendicular to the top surface of the substrate.