METHOD AND APPARATUS FOR TESTING BATCH FABRICATED MAGNETIC HEADS DURING MANUFACTURE UTILIZING MAGNETIC FIELDS GENERATED BY OTHER MAGNETIC HEADS

摘要

Magnetic head elements are batch fabricated on areas of a substrate. During manufacture, and before final separation and processing of the areas into discrete multi-track magnetic heads, defective areas are identified for removal. An electric signal source subjects the head areas to a magnetic field which is detected as electric current in each head area. The detected current value in acceptable head areas falls within a predefined range. All head areas having a current outside the range are defined as defective. The magnetic field emanates from one set of head areas in the vicinity of another set of head areas being tested.