Abstract: An anti-parallel pinned sensor is provided with a spacer that increases the anti-parallel coupling strength of the sensor. The anti-parallel pinned sensor is a GMR or TMR sensor having a pure ruthenium or ruthenium alloy spacer. The thickness of the spacer is less than 0.8 nm, preferably between 0.1 and 0.6 nm. The spacer is also annealed in a magnetic field that is 1.5 Tesla or higher, and preferably greater than 5 Tesla. This design yields unexpected results by more than tripling the pinning field over that of typical AP-pinned GMR and TMR sensors that utilize ruthenium spacers which are 0.8 nm thick and annealed in a relatively low magnetic field of approximately 1.3 Tesla.

Abstract: A magnetoresistive sensor having a substrate that has been treated with nitrogen (nitrogenated) and having a Ta cap layer with nitrogen added in situ during deposition. The nitrogenated substrate includes an alumina base layer and a thin top layer of crystalline alumina that has had a very small amount of nitrogen deposited on top. The amount of nitrogen deposited on top of the alumina is less than or equal to two monolayer, and is preferably less than on monolayer. The amount of nitrogen deposited on top of the alumina substrate is riot enough to constitute a layer of nitrogen, but affects the structure of the alumina to cause the alumina to have a desired crystalline structure and an extremely smooth surface. The nitrogen in the cap layer can be formed by depositing a Ta cap layer in a sputter deposition chamber having a small amount of nitrogen in an Ar atmosphere.

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: A magnetic head including a spin valve sensor having a sensor layer stack that includes a pinned magnetic layer, a spacer layer formed on the pinned magnetic layer, and a free magnetic layer formed on the spacer layer. In a preferred embodiment the spacer layer is comprised of CuOx. Plasma smoothing of the upper surface of the pinned magnetic layer is conducted prior to depositing the spacer layer, and a preferred plasma gas is a mixture of argon and oxygen.

Abstract: A magnetic head and magnetic storage system containing such a head, the head including a free layer and a layer of metal oxide substantially epitaxially formed relative to the free layer. Preferably, the layer of metal oxide is a crystalline structure, and is of ZnO.

Abstract: A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe—Hf—O and the Ms? of the flux guide layer is greater than 50 times the Ms? of the read sensor layer where the read sensor layer is NiFe, Ms is saturation magnetization and ? is resistivity. Because of the flux guides high resistance current shunting losses are nearly eliminated.

Abstract: A magnetic head has highly thermally conductive insulator materials containing cobalt-oxide so that heat can more effectively dissipate from the magnetic head. In one illustrative example, the magnetic head has first and second gap layers and a read sensor disposed between the first and the second gap layers. The first and the second gap layers are advantageously made of cobalt-oxide (CoOx) (e.g. CoO or Co2O3), which may exhibit a thermal conductivity of between 5-8 watts/meter-Kelvin or greater. In another illustrative example, a magnetic head is made of a substrate; first and second shield layers; an undercoat layer formed between the substrate and the first shield layer; first and second gap layers formed between the first and the second shield layers; and a read sensor formed between the first and the second gap layers. The undercoat layer is also made of CoOx.

Abstract: A magnetic head including a spin valve sensor having a sensor layer stack that includes a pinned magnetic layer, a spacer layer formed on the pinned magnetic layer, and a free magnetic layer formed on the spacer layer. In a preferred embodiment the spacer layer is comprised of CuOx. Plasma smoothing of the upper surface of the pinned magnetic layer is conducted prior to depositing the spacer layer, and a preferred plasma gas is a mixture of argon and oxygen.

Abstract: A read head is provided having having ultrathin read gap layers with improved insulative properties between a magnetoresistive sensor and ferromagnetic shield layers. The read head comprises a magnetoresistive sensor with first and second shield cap layers made of high resistivity permeable magnetic material formed between the first and second ferromagnetic shields and the first and second insulative read gap layers, respectively. The shield cap layers made of Fe—Hf—Ox material, or alternatively, the Mn—Zn ferrite material provide highly resistive or insulating soft ferromagnetic layers which add to the electrically insulative read gap layers to provide increased electrical insulation of the spin valve sensor from the metallic ferromagnetic shields while not adding to the magnetic read gap of the read head.

Abstract: A magnetic head including a spin valve sensor having a sensor layer stack that includes a pinned magnetic layer, a spacer layer formed on the pinned magnetic layer, and a free magnetic layer formed on the spacer layer. In a preferred embodiment the spacer layer is comprised of CuOx. Plasma smoothing of the upper surface of the pinned magnetic layer is conducted prior to depositing the spacer layer, and a preferred plasma gas is a mixture of argon and oxygen.

Abstract: A magnetic head has highly thermally conductive insulator materials containing cobalt-oxide so that heat can more effectively dissipate from the magnetic head. In one illustrative example, the magnetic head has first and second gap layers and a read sensor disposed between the first and the second gap layers. The first and the second gap layers are advantageously made of cobalt-oxide (CoOx) (e.g. CoO or Co2O3), which may exhibit a thermal conductivity of between 5-8 watts/meter-Kelvin or greater. In another illustrative example, a magnetic head is made of a substrate; first and second shield layers; an undercoat layer formed between the substrate and the first shield layer; first and second gap layers formed between the first and the second shield layers; and a read sensor formed between the first and the second gap layers. The undercoat layer is also made of CoOx.

Abstract: A read head is provided having having ultrathin read gap layers with improved insulative properties between a magnetoresistive sensor and ferromagnetic shield layers. The read head comprises a magnetoresistive sensor with first and second shield cap layers made of high resistivity permeable magnetic material formed between the first and second ferromagnetic shields and the first and second insulative read gap layers, respectively. The shield cap layers made of Fe—Hf—Ox material, or alternatively, the Mn—Zn ferrite material provide highly resistive or insulating soft ferromagnetic layers which add to the electrically insulative read gap layers to provide increased electrical insulation of the spin valve sensor from the metallic ferromagnetic shields while not adding to the magnetic read gap of the read head.

Abstract: An SV sensor with the preferred structure Substrate/Seed/Free/Spacer/Pinned/AFM/Cap where the seed layer is a non-magnetic Ni—Fe—Cr or Ni—Cr film and the AFM layer is preferably Ni—Mn. The non-magnetic Ni—Fe—Cr seed layer results in improved grain structure in the deposited layers enhancing the GMR coefficients and the thermal stability of the SV sensors. The improved thermal stability enables use of Ni—Mn with its high blocking temperature and strong pinning field as the AFM layer material without SV sensor performance degradation from the high temperature anneal step needed to develop the desired exchange coupling.

Abstract: A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe-Hf-O and the Ms&rgr; of the flux guide layer is greater than 50 times the Ms&rgr; of the read sensor layer where the read sensor layer is NiFe, Ms is saturation magnetization and &rgr; is resistivity. Because of the flux guides high resistance current shunting losses are nearly eliminated.

Abstract: A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe—Hf—O and the Ms&rgr; of the flux guide layer is greater than 50 times the Ms&rgr; of the read sensor layer where the read sensor layer is NiFe, Ms is saturation magnetization and &rgr; is resistivity. Because of the flux guides high resistance current shunting losses are nearly eliminated.

Abstract: An SV sensor with the preferred structure Substrate/Seed/Free/Spacer/Pinned/AFM/Cap where the seed layer is a non-magnetic Ni--Fe--Cr or Ni--Cr film and the AFM layer is preferably Ni--Mn. The non-magnetic Ni--Fe--Cr seed layer results in improved grain structure in the deposited layers enhancing the GMR coefficients and the thermal stability of the SV sensors. The improved thermal stability enables use of Ni--Mn with its high blocking temperature and strong pinning field as the AFM layer material without SV sensor performance degradation from the high temperature anneal step needed to develop the desired exchange coupling.

Abstract: An MR sensor with an improved MR coefficient and improved thermal stability is provided by employing one or more chromium based spacer layers which are interfacially adjacent a Permalloy (NiFe) stripe. The chromium based spacer layers may be NiFeCr or NiCr. The best compositions have been found to be (Ni.sub.89 Fe.sub.21).sub.60 Cr.sub.40 and Ni.sub.60 Cr.sub.40. For NiCr the MR coefficient of the MR stripe is most enhanced when the NiCr layer is deposited on a layer of tantalum (Ta). Further, when the thicknesses of the NiFeCr and the NiCr layers are 25 .ANG. and 50 .ANG. respectively the MR coefficients are optimized. Both spacer layers have a high resistance compatible with low shunting of the sense current.

Abstract: Aluminum microcircuits which have been prepared by reactive-ion etching are stabilized against open circuits and short circuits by treating the microcircuits in an oxygen-containing atmosphere at a temperature of from about 200.degree. C. to about 450.degree. C.