Patent ID: 8184398

Claim:
A magnetic head comprising: a medium facing surface that faces toward a recording medium; a coil including a winding portion having two side surfaces, the coil 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, the pole layer allowing a magnetic flux corresponding to the magnetic field generated by the coil to pass and generating a write magnetic field for writing the data on the recording medium by means of a perpendicular magnetic recording system; a shield formed of a magnetic material; a gap layer formed of a nonmagnetic material; and a coil adjacent layer that is adjacent to at least part of the whole of the two side surfaces of the winding portion, wherein: the shield has an end face located in the medium facing surface at a position forward of the end face of the pole layer along a direction of travel of the recording medium; the gap layer is disposed between the pole layer and the shield; the shield includes a plurality of layers; one of the plurality of layers of the shield is located between the coil and the medium facing surface; the coil adjacent layer has a first groove that accommodates the one of the plurality of layers of the shield, and a second groove that accommodates at least part of the winding portion; and the coil adjacent layer is formed of a nonmagnetic material having a linear thermal expansion coefficient of 5×10 −6 / ° C. or smaller at a temperature of 25° C. to 100° C. and having a thermal conductivity of 40 W/m·K or higher at a temperature of 25° C.