Abstract: A significantly thinner boron carbide overcoat layer is provided for a magnetic disk which has the same durability as thicker prior art overcoat layers for protecting an underlying magnetic layer. By employing adhesion layers selected from the group consisting of Ge, Ru, WTiSi, WTi, Si, and Y between the magnetic layer and the overcoat layer, the durability of the overcoat layer is significantly increased over a single overcoat layer of B4C. Certain process steps in the making of the B4C overcoat layer still further enhance the durability of the B4C overcoat layer by maintaining the disk or substrate specimen at a floating potential in a plasma chamber and employing low levels of argon pressure and sputtering wattage.

Abstract: A high-density recording media comprising longitudinally oriented polycrystalline barium ferrite exhibits large coercivity, corrosion resistance, high hardness and durability. Films are prepared by on-axis sputtering at ambient temperatures from stoichiometric targets followed by a post-deposition anneal at approximately 850.degree.C. to induce crystallization. Crystallization yields a magnetic film with large in-plane remanence and a fine scale texturing that greatly improves the tribological performance of barium ferrite disks. Exceptional durability can be achieved on disks without overcoats. Grain sizes as small as 200 .ANG. are produced by doping with small amounts of Cr.sub.2 O.sub.3 or other additives. Coercivities greater than 4000 Oe are achieved even in small grain films.

Abstract: A lapping control system for a row of thin film magnetic transducers formed on a substrate. Each of the magnetic transducers comprises a magnetoresistive (MR) element, and the row is supported on a holder which has an elongated H-shaped slot near one edge to form a beam member upon which the row is mounted. The beam member is capable of being deflected in a substantially quadratic curvature when subjected to pressure from a pressure transducer at the middle of the beam member. The resistance of each of the MR elements is measured during lapping, and a control signal is generated to control the pressure transducers to control lapping with proper BALANCE and BOW and to terminate lapping when the desired MR element height is reached.