ELEKTRISCHE LAPPUNGSFUEHRUNG ZUR STEUERUNG DER MENGENANFERTIGUNG VON MAGNETISCHEN DUENNFILM-WANDLERN.

摘要

Method and apparatus for controlling the throat height of batch fabricated thin film magnetic transducers (12). During deposition of the transducer elements (12) on a substrate (10), a resistive electrical lapping guide (14, 16) is deposited on at least one end of the array of transducer elements. The electrical lapping guide (14, 16) includes a plurality of switching junctions (42-48) formed between a section of electrically resistive material (32, 34) and conductors (36-40). At least one switching junction is deposited on the substrate having a known switching plane position. During lapping of the transducer pole tip ends to a final height, the switching junction will change state to provide an accurate indication of the lapped throat height. The throat height, as determined from measured resistance of the lapping guide, is compared to the switching junction position at the time the switching junction changes state. Subsequent resistance measurements are calibrated in light of this comparison.