A new class of materials for use as a dielectric to separate various metallic layers within a magnetoresistive transducer. The materials include oxides of Ta, Hf, Zr, Y, Ti, or Nb. Thin films of these materials, when fabricated in accordance with the teachings of the invention, constitute dielectric films which maintain their integrity as insulators at thicknesses down to 5 nm. Additionally, the adhesion of this class of dielectrics equals or exceeds that of commonly used dielectrics.
In a tunneling magnetoresistance transducer including first and second ferromagnetic layers and a tunnel barrier layer made of insulating material sandwiched by the first and second ferromagnetic layers, the resistance of the tunnel barrier layer remains essentially constant independent of the temperature of the transducer.
A method is provided for providing extra insulation between lead layers and first and second shield layers of a read head so as to prevent electrical shorting therebetween. A sensor layer is partially formed with a capping layer of a first oxidizable metallic layer. A lead layer is formed with a second oxidizable metallic capping layer thereon. A rear edge of the partially completed sensor is then formed followed by formation of an insulation layer which seals the rear edge. The wafer, upon which the components are constructed, is then subjected to an oxygen-based plasma which oxidizes the oxidizable layers with the second oxidizable metallic layers oxidizing at a faster rate than the first oxidizable metallic layer. The second oxidized layer then provides the desired extra insulation between the lead layers and the second shield layer. The read head produced by the method includes a sensor layer and first and second lead layers. A first metal oxide layer is on the sensor layer and a sensor layer and a second metal oxide layer is on each of the first and second lead layers. The sensor layer, the first and second lead layers and the first and second metal oxide layers are located between first and second gap layers and the first and second gap layers are located between first and second shield layers.
A method is provided for providing extra insulation between lead layers and first and second shield layers of a read head so as to prevent electrical shorting therebetween. A sensor layer is partially formed with a capping layer of a first oxidizable metallic layer. A lead layer is formed with a second oxidizable metallic capping layer thereon. A rear edge of the partially completed sensor is then formed followed by formation of an insulation layer which seals the rear edge. The wafer, upon which the components are constructed, is then subjected to an oxygen-based plasma which oxidizes the oxidizable layers with the second oxidizable metallic layers oxidizing at a faster rate than the first oxidizable metallic layer. The second oxidized layer then provides the desired extra insulation between the lead layers and the second shield layer. The read head produced by the method includes a sensor layer and first and second lead layers. A first metal oxide layer is on the sensor layer and a sensor layer and a second metal oxide layer is on each of the first and second lead layers. The sensor layer, the first and second lead layers and the first and second metal oxide layers are located between first and second gap layers and the first and second gap layers are located between first and second shield layers.
In a magnetic read/write transducer, the elements of the magnetoresistive (MR) and inductive heads are shorted together and to the slider substrate to provide a low resistance, conductive path bypassing the MR sensor element and minimizing electrical current through the MR sensor element during discharge of static electric charge. The MR sensor element, the MR conductive leads, the MR magnetic shield elements and inductive pole tips exposed at the slider air bearing surface are shorted together and to the slider substrate by a layer of conductive material, such as tungsten, formed over the slider air bearing surface. The conductive layer shorts the head elements together and to the slider substrate thus protecting the head against ESD/EOS damage during subsequent handling and assembly. The conductive layer is removed by wet etching prior to placing the magnetic head into operation in a magnetic storage system.
A longitudinal bias structure to be placed adjacent a ferromagnetic free layer or a sense layer which is responsive to an external magnetic field and belongs to a magnetic sensor, for example a magnetic readback sensor such as an anisotropic magnetoresistive (AMR) sensor, giant magnetoresistive (GMR) sensor such as GMR spin valve sensor or GMR multilayer sensor or in tunnel valve sensor. The longitudinal bias structure is built up of a top ferromagnetic bias layer of first thickness t.sub.1 having a first magnetic moment M.sub.1, a bottom ferromagnetic bias layer of second thickness t.sub.2 having a second magnetic moment M.sub.2 which is anti-parallel to first magnetic moment M.sub.1 of the top ferromagnetic bias layer, and an exchange-coupling layer disposed between the top and bottom bias layers. In this configuration the top ferromagnetic bias layer and the bottom ferromagnetic bias layer are antiferromagnetically coupled by the exchange-coupling layer and the remnant magnetization thickness product of the bias structure is desirably low and equal to M.sub.1 t.sub.1 -M.sub.2 t.sub.2. The longitudinal bias structure can further include an antiferromagnetic layer next to one of the ferromagnetic bias layers to provide a pinned longitudinal bias structure.
