Patent ID: 9336798
Filing Date: 2016-05-10
CPC Classification: G11B

Claim Text:
1. A magnetic head for perpendicular magnetic recording, comprising: a medium facing surface configured to face a recording medium; a coil for producing a magnetic field corresponding to data to be written on the recording medium; a main pole for passing a magnetic flux corresponding to the magnetic field produced by the coil, and for producing a write magnetic field for use to write the data on the recording medium by means of a perpendicular magnetic recording system; a write shield formed of a magnetic material; a gap section formed 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 section are disposed above the top surface of the substrate, the write shield includes a bottom shield, a top shield, a first side shield and a second side shield, the main pole includes a main body, and a lower protrusion protruding from the main body toward the top surface of the substrate, the lower protrusion is located at a distance from the medium facing surface, the main body includes a front portion and a rear portion, the front portion being located closer to the medium facing surface than is the lower protrusion, the rear portion being located farther from the medium facing surface than is the front portion, the front portion has: an end face located in the medium facing surface; a top surface farthest from the top surface of the substrate; a bottom end opposite to the top surface; and a first side surface and a second side surface opposite to each other in a track width direction, the lower protrusion has: a front end face facing toward the medium facing surface; a bottom surface facing toward the top surface of the substrate; and a third side surface and a fourth side surface opposite to each other in the track width direction, the bottom shield is located on a rear side in a direction of travel of the recording medium relative to the front portion, the top shield is located on a front side in the direction of travel of the recording medium relative to the front portion, the first and second side shields are located on opposite sides of the front portion in the track width direction, the gap section includes a first portion interposed between the main pole and each of the bottom shield, the first side shield and the second side shield, and a second portion interposed between the main pole and the top shield, the first side shield has a first front end face located in the medium facing surface, a first sidewall opposed to the first side surface, and a first rear end face contiguous with the first sidewall and opposite to the first front end face, the second side shield has a second front end face located in the medium facing surface, a second sidewall opposed to the second side surface, and a second rear end face contiguous with the second sidewall and opposite to the second front end face, the bottom shield has a top surface farthest from the top surface of the substrate, and includes a receiving section recessed from the top surface of the bottom shield and receiving a portion of the lower protrusion, the receiving section has a front wall face opposed to the front end face of the lower protrusion, a third sidewall opposed to the third side surface, and a fourth sidewall opposed to the fourth side surface, the first sidewall has a first edge closest to the top surface of the substrate, the second sidewall has a second edge closest to the top surface of the substrate, the third sidewall has a third edge farthest from the top surface of the substrate, the fourth sidewall has a fourth edge farthest from the top surface of the substrate, the third edge is contiguous with the first edge, and the fourth edge is contiguous with the second edge.