Abstract: A magnetoresistive sensor having a hard bias structure having increased coercivity and squareness. The structure also allows the use of a thinner seed layer, which results in improved biasing by decreasing the spacing between the hard magnetic bias layer and the free layer of the sensor. The hard bias structure can be deposited over either a crystalline structure or over an amorphous material. The hard bias structure includes a hard bias material comprising CoPt deposited over a seed layer including a layer of NiTa and a layer of CrMo.

Abstract: A process for defining and controlling the track width for sensor devices is disclosed. An RIE-resistant, image layer, such as Cu or NiFe, is deposited after the DLC layer. A combination of RIE and ion milling processes or reactive ion beam etching processes are used to form the mask structure. Having an RIE-resistant layer precisely defines the DLC edge and minimizes the line edge roughness that result from fast removal of duramide during RIE. This solution controls the formation of the edges of the sensors and provides good definition for DLC mask edges. The image layer may be chemical mechanical polished to eliminate ion milling before the final RIE step.

Abstract: A process for defining and controlling the mask height of sensor devices is disclosed. An RIE-resistant, image layer, such as Cu or NiFe, is deposited after the DLC layer. A combination of RIE and ion milling processes or reactive ion beam etching processes are used to form the mask structure. Having an RIE-resistant layer precisely defines the DLC edge and minimizes the line edge roughness that result from fast removal of duramide during RIE. This solution controls the formation of the edges of the sensors and provides good definition for DLC mask edges. The image layer may be chemical mechanical polished to eliminate ion milling before the final RIE step.

Abstract: A method and apparatus for providing magnetostriction control in a free layer of a magnetic memory device is disclosed. The same target compositions for the free layers may be used, but the relative thickness values are modified to obtain a desired magnetostriction without a change in the magenetoristance ratio, ?R/R.

Abstract: A magnetic head includes a seed layer structure comprising Al2O3, Ta, and NiFeCr seed layers. An antiparallel (AP) pinned layer structure is formed above the NiFeCr seed layer. A free layer is positioned above the AP pinned layer structure.

Abstract: A spin valve (SV) sensor of the self-pinned type includes one or more compressive stress modification layers for reducing the likelihood that the pinning field will flip its direction. The spin valve sensor includes a capping layer formed over a spin valve structure which includes a free layer, an antiparallel (AP) self-pinned layer structure, and a spacer layer in between the free layer and the AP self-pinned layer structure. A compressive stress modification layer is formed above or below the capping layer, adjacent the AP self-pinned layer structure, or both. Preferably, the compressive stress modification layer is made of ruthenium (Ru) or other suitable material.

Abstract: Methods for use in forming a CPP read sensor for a magnetic head are disclosed. In a particular example, a plurality of read sensor layers are formed over a first shield layer and a resist without undercuts is formed over the plurality of read sensor layers in a central region. With the resist in place, read sensor materials in side regions adjacent the central region are removed by milling to thereby form a read sensor structure in the central region. Insulator materials and metallic seed materials are then deposited in the side regions. High angle ion milling is performed to reduce a thickness of the insulator materials, the metallic seed materials, or both, along sidewalls of the read sensor structure. Magnetic hard bias materials are subsequently deposited over the metallic seed materials, and a second shield layer is formed over the structure after the resist is removed.

Abstract: A magnetic head assembly has a read head that includes a sensor wherein the sensor includes a self-pinned antiparallel (AP) pinned layer structure, a ferromagnetic free layer structure that has a magnetic moment that is free to rotate in response to signal fields and a spacer layer which is located between the free layer and AP pinned layer structures. The self-pinned AP pinned layer structure includes first and second antiparallel (AP) pinned layers, an antiparallel coupling (APC) layer located between and interfacing the first and second AP pinned layers wherein the second AP pinned layer is located between the first AP pinned layer and the spacer layer. The first AP pinned layer is composed of cobalt platinum chromium (CoPtCr).

Abstract: In one illustrative example of the invention, a spin valve sensor of a magnetic head has a sensor stack structure which includes a free layer structure and an antiparallel (AP) pinned layer structure separated by a spacer layer. A capping layer structure formed over the sensor stack structure includes a layer of cobalt (e.g. pure cobalt, oxidized cobalt, or cobalt-iron) as well as a layer of tantalum formed over it. Advantageously, the cobalt layer in the capping layer structure enhances the GMR and soft magnetic properties for thinner freelayer structures while maintaining a desirable slightly negative magnetostriction.

Abstract: A GMR read head for a magnetic head, in which the hard bias layers are fabricated immediately next to the side edges of the free magnetic layer, and such that the midplane of the hard bias layer and the midplane of the free magnetic layer are approximately coplanar. The positioning of the hard bias layer is achieved by depositing a thick hard bias seed layer, followed by an ion milling step is to remove seed layer sidewall deposits. Thereafter, the hard bias layer is deposited on top of the thick seed layer. Alternatively, a first portion of the hard bias seed layer is deposited, followed by an ion milling step to remove sidewall deposits. A thin second portion of the seed layer is next deposited, and the hard bias layer is then deposited.

Abstract: In one illustrative example of the invention, a spin valve sensor includes a free layer structure; an antiparallel (AP) pinned layer structure; and a non-magnetic electrically conductive spacer layer in between the free layer structure and the AP pinned layer structure. The AP pinned layer structure includes a first AP pinned layer; a second AP pinned layer; and an antiparallel coupling (APC) layer formed between the first and the second AP pinned layer. One of the first and the second AP pinned layers consists of cobalt and the other one includes cobalt-iron. The pure cobalt may be provided in the first AP pinned layer or the second AP pinned layer. Advantageously, the use of cobalt in one of the AP pinned layers increases the ?r/R of the spin valve sensor.

Abstract: In one illustrative embodiment of the invention, a spin valve sensor of a magnetic head has a free layer structure; an antiparallel (AP) self-pinned layer structure; and a non-magnetic electrically conductive spacer layer in between the free layer structure and the AP self-pinned layer structure. The AP self-pinned layer structure includes a first AP pinned layer; a second AP pinned layer; an antiparallel coupling (APC) layer formed between the first and the second AP pinned layers. At least one of the first and the second AP pinned layers is made of cobalt having no iron content. The other AP pinned layer may be formed of cobalt, cobalt-iron, or other suitable material. The use of cobalt in the AP self-pinned layer structure increases its magnetostriction to increase the self-pinning effect. Preferably, the first AP pinned layer is cobalt-iron and the second AP pinned layer is cobalt which provides for both an increase in magnetostriction and magnetoresistive coefficient ?r/R of the sensor.

Abstract: A method for improving hard bias properties of layers of a magnetoresistance sensor is disclosed. Properties of the hard bias layer are improved using a seedlayer structure that includes at least a first layer of silicon and a second layer comprising chromium or chromium molybdenum. Further, benefits are achieved when the seedlayer structure includes a layer of tantalum.

Abstract: A tunnel junction having reduced free layer coercivity for improved sensitivity. The tunnel valve has a free layer that has been deposited in the presence of a nitrogen gas, which reduces the coercivity of the free layer, thereby improving the sensor's sensitivity and performance.

Abstract: A magnetic head including an electrical lead layer that is comprised of a material having an ordered crystalline structure. In a preferred embodiment, the ordered crystalline structure of the electrical lead is epitaxially matched to the crystalline structure of the hard bias layer upon which it is formed, and there is no need for a seed layer for the electrical leads. Electrical leads having an ordered crystalline structure, particularly a B2, L10, L11, L12 and D03 structure, will have significantly reduced resistivity over the prior art electrical leads that are typically composed of rhodium or tantalum. As a result, thinner electrical leads can be fabricated which carry the same, or even greater, current than the prior art rhodium or tantalum leads. The preferred leads are comprised of NiAl having a B2 crystalline structure, and alternative embodiments are comprised of CuAu, Cu3Au, Ni3Al and Fe3Al.

Abstract: The magnetic head of the present invention includes a magnetoresistive read head element in which a magnetic bias layer is deposited across the surface of the wafer above the free magnetic layer. Central portions of the biasing layer that correspond to the read head track width are oxidized to essentially remove the magnetic moment of the bias layer material in those central locations. An oxygen diffusion barrier layer is then deposited upon the oxidized central portions of the biasing layer to prevent diffusion or migration of oxygen from the oxidized central regions of the biasing layer. An insulation layer, a second magnetic shield layer and further structures of the magnetic head are subsequently fabricated.

Abstract: A magnetoresistive sensor having bias stabilization tabs includes a protective cap layer. The protective cap layer prevents oxidation, avoids potential damage from using ion milling for oxidation removal, and lowers parasitic resistance. In one embodiment, a bias layer, having a central portion with quenched magnetic moment, is formed over the free layer with an intervening coupling layer. A disk drive is provided with the magnetoresistive sensor including a protective cap layer.

Abstract: A lead overlay magnetoresistive sensor has leads with substantially vertical end walls to accentuate sense current near the ends of the leads. Insulating layers isolate the hard bias layers from the path of the sense current. A lead overlay magnetoresistive sensor does not exhibit significant trackwidth widening. A disk drive has a read element including a lead overlay magnetoresistive sensor with leads having substantially vertical end walls.

Abstract: In a magnetic head a read sensor is located between first and second read gap layers wherein the first read gap layer includes a read gap material layer and first and second refill gap layers. The read gap material layer has first and second depressions which extend laterally from the first and second side walls respectively of the sensor and the first and second refill gap layers are disposed in the first and second depressions and engage a bottom portion of the first side wall and engage a bottom portion of the second side wall respectively. The first read gap layer has first and second portions which extend laterally from the first and second side walls of the sensor and a third portion which engages a bottom surface of the sensor and is located between said first and second portions with each of said first and second portions having a thickness which is greater than a thickness of said third portion.

Abstract: A magnetic read head has a current perpendicular to the planes (CPP) sensor with a top cap layer that is ruthenium (Ru) or rhodium (Rh) or a top cap layer structure which includes a first layer of tantulum (Ta) only, a second layer of ruthenium (Ru), rhodium (Rh) or gold (Au) with the first layer being located between a spacer layer and the second layer.