Patent ID: 8138754
Filing Date: 2012-03-20
Classification: G11B

Abstract:
1. A method for testing characteristics of a thin-film magnetic head, the method using a sensor unit having a magnetic sensor and testing a bar integrally including a plurality of thin-film magnetic heads which are arranged in a row and each of which includes a write element and a read element, the bar being severable into a plurality of sliders, each slider including one of the thin-film magnetic heads, wherein first and second directions are parallel to a magnetic-field-generating surface of the write element, and a third direction is perpendicular to the first and second directions, the method comprising: moving, in the third direction, position of the sensor unit relative to a predetermined write element on the bar while the sensor unit is fixed at a predetermined position with respect to the first and second directions, and, at the same time, measuring with the magnetic sensor the magnetic field generated by the predetermined write element, and fixing the position of the sensor unit relative to the predetermined write element with respect to the third direction, so that the magnetic field measured by the magnetic sensor at the predetermined position, with respect to the first and second directions, satisfies a predetermined condition; changing in the first and second directions, within a predetermined area, the position of the sensor unit relative to the predetermined write element, while maintaining fixed the relative position with respect to the third direction; after changing the position of the sensor unit, measuring, with the magnetic sensor, the magnetic field generated by the predetermined write element; repeating the foregoing three steps a predetermined number of times and evaluating characteristics of the predetermined write element based on the magnetic fields measured by the magnetic sensor at each of the relative positions, with respect to the first and second directions; and repeating the foregoing four steps for each of the plurality of write elements included in the bar.