Patent ID: 7369361

Claim:
A magnetic head substructure used for manufacturing magnetic heads, each of the magnetic heads comprising: a medium facing surface that faces toward a recording medium; a magnetoresistive element that has an end located in the medium facing surface and reads data stored on the recording medium; a coil that generates a magnetic field corresponding to data to be written on the recording medium; and a pole layer that incorporates a track width defining portion having an end face located in the medium facing surface, allows a magnetic flux corresponding to the field generated by the coil to pass therethrough, and generates a write magnetic field for writing the data on the recording medium, the substructure comprising: a substrate; a plurality of sets of the magnetoresistive element, the pole layer and the coil formed in the substrate such that a plurality of rows of pre-head portions that will be the respective magnetic heads later are aligned; and resistor elements each of which is located such that a portion thereof is exposed at the medium facing surface when the medium facing surface is formed, and each of which has a resistance that varies depending on a location of the end face of the track width defining portion along the direction orthogonal to the medium facing surface when the medium facing surface is formed, wherein a distance between each of the resistor elements and the substrate is closer to a distance between the track width defining portion and the substrate than a distance between the magnetoresistive element and the substrate, and a resistance value of each of the resistor elements obtained after the medium facing surfaces are formed corresponds to a length of the track width defining portion taken in the direction orthogonal to the medium facing surfaces.