Abstract: Disclosed is a spin-valve sensor disposed between first and second gap layers and formed of one or more in-situ oxidized films. The improved spin valve sensor helps eliminate electrical shorting between the spin-valve sensor and shield layers. A fabrication method of the gap layers comprises repeatedly depositing a metallic films on a wafer in a DC-magnetron sputtering module of a sputtering system, and then transferring the wafer in a vacuum to an oxidation module where in-situ oxidation is conducted. This deposition/in-situ oxidation process is repeated until a designed thicknesses of gap layers is attained. Smaller, more sensitive spin-valve sensors may be sandwiched between thinner gap layers formed of in-situ oxidized films, thus allowing for greater recording data densities in disk drive systems.

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 method is described comprising forming an insulating polycrystalline seed layer in a first chamber by reactively pulsed DC magnetron sputtering, then forming an insulating amorphous-like seed layer in a second chamber by reactively pulsed DC magnetron sputtering, then forming a conducting seed layer and a ferromagnetic free layer in a third chamber by ion beam sputtering, and then forming the remainder of a spin valve sensor through the antiferromagnetic layer in a fourth chamber by DC magnetron sputtering.

Abstract: A trilayer seed layer structure is employed between a first read gap layer and a spin valve sensor for improving the magnetic and giant magnetoresistive properties and the thermal stability. In the spin valve sensor, the trilayer seed layer structure is located between a first read gap layer and a ferromagnetic free layer. The antiferromagnetic pinning layer is preferably nickel manganese (Ni—Mn). The trilayer seed layer structure includes a first seed layer that is a first metallic oxide, a second seed layer that is a second metallic oxide and a third seed layer that is a nonmagnetic metal.

Abstract: A trilayer seed layer structure is employed between a first read gap layer and a spin valve sensor for improving the magnetic and giant magnetoresistive properties and the thermal stability. In the spin valve sensor, the trilayer seed layer structure is located between a first read gap layer and a ferromagnetic free layer. The antiferromagnetic pinning layer is preferably nickel manganese (Ni—Mn). The trilayer seed layer structure includes a first seed layer that is a first metallic oxide, a second seed layer that is a second metallic oxide and a third seed layer that is a nonmagnetic metal. A preferred embodiment is a first seed layer of nickel oxide (NiO), a second seed layer of nickel manganese oxide (NiMnOx), and a third seed layer of copper (Cu).

Abstract: A spin valve sensor is provided with a keeper layer which forms a partial flux-closure with a reference layer so as to minimize sensitivity of readback signal asymmetry to the sensor stripe height while maintaining a high readback signal. The keeper layer is encapsulated with top and bottom oxide layers, as well as first and second side oxide layers which form contiguous junctions with first and second side edges of the keeper layer. The top oxide layer may be a seed layer for the spin valve sensor for improving its giant magnetoresistance properties. The bottom oxide layer may be an antiferromagnetic film for pinning the magnetic moment of the keeper layer. The first and second side oxide layers function as refill first gap layers for minimizing the risk of electrical shorts between the bottom shield layer and the first and second hard bias and lead layers of the read head.

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 antiferromagnetic stabilization scheme is employed in a magnetic head for magnetically stabilizing a free layer of a spin valve. This is accomplished by utilizing an antiferromagnetic oxide film below a spin valve sensor in a read region and first and second lead layers in end regions and a ferromagnetic film in each of the lead layers that exchange couples to the antiferromagnetic oxide film in the end regions. The ferromagnetic films are pinned with their magnetic moments oriented parallel to an air bearing surface (ABS) of the magnetic head. The ferromagnetic films magnetostatically couple to the free layer which causes the free layer to be in a single magnetic domain state. Accordingly, when the free layer is subjected to magnetic incursions from a rotating disk in a disk drive, the free layer maintains a stable magnetic condition so that resistance changes of the free layer are not altered by differing magnetic conditions of the free layer.

Abstract: An SV sensor with the preferred structure Substrate/Seed/Free/Spacer/Pinned/AFM/Cap where the seed and cap layers are formed of a non-magnetic, electrically insulating oxide, NiMnOx. The non-magnetic electrically insulating NiMnOx seed layer results in enhanced GMR coefficient and improved thermal stability of the SV sensor. The improved thermal stability enables use of Ni—Mn with its high blocking temperature and strong pinning field as the AFM layer material, as well as other Mn alloys, without SV sensor performance degradation from the high temperature anneal step needed to develop the desired exchange coupling. The electrically insulating property of the NiMnOx seed and cap layer material decreases sense current shunting and further reduces shield/sensor shorting.

Abstract: A fully-pinned, flux-closed spin valve (SV) magnetoresistive sensor having a reference (pinned) layer with magnetization fixed by a first antiferromagnetic (AFM1) layer, and a keeper layer with magnetization fixed by a second antiferromagnetic (AFM2) layer. The magnetization of the keeper layer is saturated and fixed in an antiparallel orientation to the pinned layer magnetization by an exchange interaction with the AFM2 layer. The magnetic moments of the pinned layer and the keeper layer are approximately matched to form a flux-closed magnetic configuration wherein demagnetizing fields in the pinned layer are largely canceled and magnetostatic interaction with the free layer is reduced. Saturation of the keeper layer magnetization by exchange coupling with the AFM2 layer eliminates or reduces magnetization canting at the edges of the keeper layer which can result in signal field shunting through the keeper layer.

Abstract: An MR read head has first and second lead layers protected by first, second and third insulation layers in addition to the first and second insulative gap layers substantially all the way from the side edges of an MR sensor to terminals. The first and second insulation layers do not extend outside of the first and second lead layer sites so that greater heat dissipation can be realized from the MR sensor. Each lead layer comprises first and second lead layer films. Where these films overlap for electrical connection their top and bottom surfaces are protected by the first and second insulation layers and their edges are protected by the third insulation layer. Where the first lead layer film extends from the second lead layer film toward the respective terminal its bottom surface is protected by the first insulation layer and its top surface and its side edges are protected by the third insulation layer. Only three masks are required for fabricating or constructing these components.

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 SV sensor having a reference (pinned) layer formed of a first high uniaxial anisotropy ferromagnetic material, such as Co--Fe, and a keeper layer formed of a second high uniaxial anisotropy ferromagnetic material, such as Ni--Fe--Nb. Lapping induced stress in the Co--Fe layer having high positive magnetostriction generates a stress-induced uniaxial anisotropy field in the reference layer resulting in enhanced reference layer magnetization. This uniaxial anisotropy field is capable by itself of maintaining a substantial transverse reference layer saturation even at elevated temperatures. Lapping induced stress in the Ni--Fe--Nb layer having high positive magnetostriction generates a stress-induced uniaxial anisotropy field in the keeper layer providing more uniform magnetization and therefore better flux cancellation. The high electrical resistivity of the Ni--Fe--Nb keeper layer has the further benefit of reducing sense current shunting by the keeper layer.

Abstract: An SV sensor having a reference (pinned) layer formed of a first high uniaxial anisotropy ferromagnetic material, such as Co--Fe, and a keeper layer formed of a second high uniaxial anisotropy ferromagnetic material, such as Ni--Fe--Nb. Lapping induced stress in the high positive magnetostriction Co--Fe layer generates a uniaxial anisotropy field in the pinned layer resulting in enhanced pinned layer magnetization. This uniaxial anisotropy field adds to the exchange field from an antiferromagnetic layer resulting in a substantially increased pinning field over the pinning field from the exhange interaction alone. The added uniaxial anisotropy field also improves the stability of the SV sensor at elevated temperatures since the uniaxial field is determined by a Curie temperature significantly higher than the blocking temperatures of antiferromagnetic materials.

Abstract: Disclosed are spin valve magnetoresistive heads, air bearing sliders and magnetic storage systems employing spin valve magnetoresistive heads, and methods for fabricating spin valve magnetoresistive heads and air bearing sliders employing spin valve magnetoresistive heads. The spin valve magnetoresistive head in accordance with the present invention employs two antiferromagnetic films, one exchange-coupling to the reference layer in a first direction in the read region and the other exchange-coupling to the ferromagnetic film in a second direction substantially perpendicular to the first direction in the end regions. The exchange-coupled reference layer and the first antiferromagnetic film exhibit a blocking temperature equal to or greater than 300.degree. C. The exchange-coupled ferromagnetic/second antiferromagnetic films exhibit a blocking temperature equal to or greater than 200.degree. C. The two high blocking temperatures ensure thermal stabilty during sensor operation.

Abstract: A spin valve (SV) sensor having a Ni-Mn antiferromagnetic (AFM) layer, a pinned layer, a free layer and a spacer layer disposed between said free and pinned layers. The pinned layer is formed over and in contact with the antiferromagnetic (AFM) Ni-Mn layer where the combination of the AFM and pinned layers is first annealed before depositing the rest of the SV layers. Carrying out the annealing process of the combination of the AFM and pinned layers prior to deposition of the rest of the SV layers provides the exchange coupling field necessary to pin the pinned layer while avoiding thermal degradation of the SV sensor giant magnetoresistive effect.

Abstract: A magnetoresistive (MR) head and a method are disclosed providing a longitudinal bias layer and conductor leads at end regions of sensor elements to form a sensor region between the end regions. A uniform longitudinal bias thin film layer is deposited overlaying the entirety of the upper MR sensor, and a uniform conductor thin film layer is deposited overlaying the entirety of the longitudinal bias thin film layer. A photoresist process is conducted over the conductor thin film layer to develop a mask of the end regions and to expose a central region between the end regions.

Abstract: A magnetic tunnel junction (MTJ) magnetoresistive (MR) read head has one fixed ferromagnetic layer and one sensing ferromagnetic layer on opposite sides of the tunnel barrier layer, and with a biasing ferromagnetic layer in the MTJ stack of layers that is magnetostatically coupled with the sensing ferromagnetic layer to provide either longitudinal bias or transverse bias or a combination of longitudinal and transverse bias fields to the sensing ferromagnetic layer. The magnetic tunnel junction in the MTJ MR head is formed on an electrical lead on a substrate and is made up of a stack of layers.

Abstract: A spin valve (SV) sensor having a Ni--Mn antiferromagnetic (AFM) layer, a pinned layer, a free layer and a spacer layer disposed between said free and pinned layers. The pinned layer is formed over and in contact with the antiferromagnetic (AFM) Ni--Mn layer where the combination of the AFM and pinned layers is first annealed before depositing the rest of the SV layers. Carrying out the annealing process of the combination of the AFM and pinned layers prior to deposition of the rest of the SV layers provides the exchange coupling field necessary to pin the pinned layer while avoiding thermal degradation of the SV sensor giant magnetoresistive effect.