Abstract: A discrete track thin film metal alloy or metal oxide magnetic recording disk is fabricated by forming a thin film of magnetic material on a substrate, patterning the magnetic film with a chemically etchable support layer and a high resolution photoresist layer, removing portions of the magnetic film and refilling with nonmagnetic material to form concentric nonmagnetic guard bands, and then applying a top layer of additional nonmagnetic material as a passivating and protective disk overcoat after removal of the remaining support layer and photoresist. The exposed photoresist and portions of the chemically etchable support layer beneath the side walls of the patterned photoresist defining the edges of the magnetic tracks are removed in a photoresist developer which also creates undercuts in the support layer beneath the side walls. The undercuts prevent "fences" and provide smooth interfaces between the magnetic tracks and the nonmagnetic guard bands.

Abstract: A magnetoresistive (MR) read transducer assembly in which the thin film MR layer is longitudinally biased only in the passive regions by exchange bias developed by a thin film of antiferromagnetic material that is deposited in direct contact with and continuously covering a thin film of soft magnetic material which extends across the transducer assembly. The longitudinal bias is developed by exchange coupling between the thin film of antiferromagnetic material and both the MR layer and the thin film of soft magnetic material in the passive regions. However, the thin film of soft magnetic material is separated from the MR layer in the active region only of the MR layer by a decoupling layer which interrupts the exchange coupling so that transverse bias is produced only in the active region upon connection of a bias source to conductor leads which are connected to the MR layer within the passive region.

Abstract: A magnetoresistive (MR) read head in which an insulator layer defines the effective track width over which the read head is sensitive. The insulator layer is deposited or patterned to extend a predetermined distance over the MR element, and the predetermined distance is chosen equal to the desired track width. Conductor leads are deposited in contact with the regions of the MR element not covered by the insulator layer with the conductor leads extending up to, and possibly overlapping, the edges of the insulator layer so that the read signal is sensed over the length of the MR element covered by the insulator layer.

Abstract: A magnetoresistive (MR) read transducer assembly in which the thin film MR layer is longitudinally biased only in the end regions by exchange bias developed by a thin film of antiferromagnetic material that is deposited in direct contact only in the end regions of the MR layer and a thin film of soft magnetic material which extends across the transducer assembly. The longitudinal bias is developed by exchange coupling between the thin film of antiferromagnetic material and both the MR layer and the thin film of soft magnetic material in the end regions. However, the thin film of soft magnetic material is separated from the MR layer in the central region only of the MR layer by a decoupling layer which interrupts the exchange coupling so that transverse bias is produced only in the central region upon connection of a bias source to conductor leads which are connected to the MR layer within the end region.

Abstract: Via holes are etched in an alumina layer using an etchant bath of ethylenediaminetetraacetic acid at a pH above 9.