Abstract: Embodiments disclosed herein generally relate to a magnetic head having an amorphous ferromagnetic reference layer. The ferromagnetic reference layer may have amorphous structure as a result of an amorphous ferromagnetic underlayer that the ferromagnetic reference layer is deposited thereon. The amorphous ferromagnetic reference layer enhances magnetoresistance, leading to an improved magnetic head.

Abstract: Embodiments disclosed herein generally relate to a magnetic head having an amorphous ferromagnetic reference layer. The ferromagnetic reference layer may have amorphous structure as a result of an amorphous ferromagnetic underlayer that the ferromagnetic reference layer is deposited thereon. The amorphous ferromagnetic reference layer enhances magnetoresistance, leading to an improved magnetic head.

Abstract: A disk drive includes a disk including a magnetizable layer of material, and a transducer. The transducer has a read element that includes a first shield layer, a pinned layer, a metallic spacer, an AP (anti-parallel) free layer, and a second shield layer. The pinned layer has a surface area which is greater than the area of the AP free layer. The read element also includes an anti-ferromagnetic layer for substantially fixing the magnetic orientation of a plurality of domains in the pinned layer. The ferromagnetic layer is adjacent the pinned layer. The pinned layer, and the anti-ferromagnetic layer both have surface areas which are greater than the area associated with the AP free layer. The anti-ferromagnetic layer, in one embodiment, has a pinning strength in the range of 0.5 erg/cm2 to 1.5 erg/cm2.

Abstract: A current-perpendicular-to-the-plane giant magnetoresistance (CPP-GMR) has a multilayer reference layer containing a Heusler alloy. The multilayer reference layer includes a crystalline non-Heusler alloy ferromagnetic layer on an antiferromagnetic layer, a Heusler alloy layer, and an intermediate crystalline non-Heusler alloy of the form CoFeX, where X is one or more of Ge, Al, Si and Ga, located between the non-Heusler alloy layer and the Heusler alloy layer. The CoFeX alloy layer has a composition (CoyFe(100-y))zX(100-z) where y is between about 10 and 90 atomic percent, and z is between about 50 and 90 atomic percent. The CoFeX alloy layer induces very strong pinning, which greatly lessens the likelihood of magnetic instability by the spin polarized electron flow from the free layer to the reference layer.

Abstract: A current-perpendicular-to-the-plane magnetoresistive sensor has an antiparallel free (APF) structure and soft side shields wherein the upper free layer (FL2) of the APF structure is magnetically coupled antiparallel to the top shield and a top shield seed layer via a nonmagnetic antiparallel coupling (APC) layer. In one embodiment the antiparallel coupling is through an antiferromagnetic-coupling (AFC) layer that provides a dominant antiferromagnetic indirect exchange coupling of FL2 to the top shield. In another embodiment the antiparallel coupling is by an APC layer that decouples FL2 and the top shield and causes the edge-induced magnetostatic coupling between FL2 and the seed layer to dominate. The degree of coupling is controlled by the composition and thickness of the nonmagnetic APC layer between FL2 and the seed layer, and by the thickness of the seed layer.

Abstract: A current-perpendicular-to-the-plane magnetoresistive sensor has an antiparallel free (APF) structure and soft side shields wherein the upper free layer (FL2) of the APF structure is magnetically coupled antiparallel to the top shield and a top shield seed layer via a nonmagnetic antiparallel coupling (APC) layer. In one embodiment the antiparallel coupling is through an antiferromagnetic-coupling (AFC) layer that provides a dominant antiferromagnetic indirect exchange coupling of FL2 to the top shield. In another embodiment the antiparallel coupling is by an APC layer that decouples FL2 and the top shield and causes the edge-induced magnetostatic coupling between FL2 and the seed layer to dominate. The degree of coupling is controlled by the composition and thickness of the nonmagnetic APC layer between FL2 and the seed layer, and by the thickness of the seed layer.

Abstract: A disk drive includes a disk including a magnetizable layer of material, and a transducer. The transducer has a read element that includes a first shield layer, a pinned layer, a metallic spacer, an AP (anti-parallel) free layer, and a second shield layer. The pinned layer has a surface area which is greater than the area of the AP free layer. The read element also includes an anti-ferromagnetic layer for substantially fixing the magnetic orientation of a plurality of domains in the pinned layer. The ferromagnetic layer is adjacent the pinned layer. The pinned layer, and the anti-ferromagnetic layer both have surface areas which are greater than the area associated with the AP free layer. The anti-ferromagnetic layer, in one embodiment, has a pinning strength in the range of 0.5 erg/cm2 to 1.5 erg/cm2.

Abstract: A current-perpendicular-to-the-plane giant magnetoresistance (CPP-GMR) has a multilayer reference layer containing a Heusler alloy. The multilayer reference layer includes a crystalline non-Heusler alloy ferromagnetic layer on an antiferromagnetic layer, a Heusler alloy layer, and an intermediate crystalline non-Heusler alloy of the form CoFeX, where X is one or more of Ge, Al, Si and Ga, located between the non-Heusler alloy layer and the Heusler alloy layer. The CoFeX alloy layer has a composition (CoyFe(100-y))zX(100-z) where y is between about 10 and 90 atomic percent, and z is between about 50 and 90 atomic percent. The CoFeX alloy layer induces very strong pinning, which greatly lessens the likelihood of magnetic instability by the spin polarized electron flow from the free layer to the reference layer.

Abstract: A method for making a current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) sensor that has a reference layer with low coercivity includes first depositing, within a vacuum chamber, a seed layer and an antiferromagnetic layer on a substrate without the application of heat. The substrate with deposited layers is then heated to between 200-600° C. for between 1 to 120 minutes. The substrate with deposited layers is then cooled, preferably to room temperature (i.e., below 50° C., but to at least below 100° C., in the vacuum chamber. After cooling of the antiferromagnetic layer, the ferromagnetic reference layer is deposited on the antiferromagnetic layer. Then the substrate with deposited layers is removed from the vacuum chamber and subjected to a second annealing, in the presence of a magnetic field, by heating to a temperature between 200-400° C. for between 0.5-50 hours.

Abstract: A method for making a current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) sensor that has a reference layer with low coercivity includes first depositing, within a vacuum chamber, a seed layer and an antiferromagnetic layer on a substrate without the application of heat. The substrate with deposited layers is then heated to between 200-600° C. for between 1 to 120 minutes. The substrate with deposited layers is then cooled, preferably to room temperature (i.e., below 50° C., but to at least below 100° C., in the vacuum chamber. After cooling of the antiferromagnetic layer, the ferromagnetic reference layer is deposited on the antiferromagnetic layer. Then the substrate with deposited layers is removed from the vacuum chamber and subjected to a second annealing, in the presence of a magnetic field, by heating to a temperature between 200-400° C. for between 0.5-50 hours.

Abstract: An air-bearing slider used in a magnetic recording disk drive has a surface that supports a magnetoresistive (MR) read head or sensor and an electrical lapping guide (ELG) adjacent to the MR sensor. The ELG is formed of a different material than the MR sensor so as to have both a high electrical resistivity and a substantially higher etch rate. When the ELG and MR sensor are etched simultaneously to form their respective back edges, the ELG will have a sharp well-defined non-tapered wall at the back edge. The ELG has a film thickness close to but generally thinner than that of the MR sensor, and a sheet resistance to generally match the resistance measurement capability of the lapping tool. The preferred material for the ELG is an alloy comprising silver (Ag) and one or more of Sn, Ge and zinc Zn.

Abstract: A method for making a current-perpendicular-to the-plane giant magnetoresistance (CPP-GMR) sensor with a Heusler alloy pinned layer on the sensor's Mn-containing antiferromagnetic pinning layer uses two annealing steps. A layer of a crystalline non-Heusler alloy ferromagnetic material, like Co or CoFe, is deposited on the antiferromagnetic pinning layer and a layer of an amorphous X-containing ferromagnetic alloy, like a CoFeBTa layer, is deposited on the Co or CoFe crystalline layer. After a first in-situ annealing of the amorphous X-containing ferromagnetic alloy, the Heusler alloy pinned layer is deposited on the amorphous X-containing ferromagnetic layer and a second high-temperature annealing step is performed to improve the microstructure of the Heusler alloy pinned layer.

Abstract: A current-perpendicular-to-the-plane magnetoresistive sensor has magnetic damping material located adjacent either or both of the sensor side edges and back edge to reduce the effect of spin transfer torque. The damping material may be Pt, Pd, Os, or a rare earth metal from the 15 lanthanoid elements. The damping material may be an ultrathin layer in contact with the sensor edges. An insulating layer is deposited on the damping layer and isolates the sensor's ferromagnetic biasing layer from the damping layer. Instead of being a separate layer, the damping material may be formed adjacent the sensor edges by being incorporated into the material of the insulating layer.

Abstract: A method for making a current-perpendicular-to the-plane giant magnetoresistance (CPP-GMR) sensor with a Heusler alloy pinned layer on the sensor's Mn-containing antiferromagnetic pinning layer uses two annealing steps. A layer of a crystalline non-Heusler alloy ferromagnetic material, like Co or CoFe, is deposited on the antiferromagnetic pinning layer and a layer of an amorphous X-containing ferromagnetic alloy, like a CoFeBTa layer, is deposited on the Co or CoFe crystalline layer. After a first in-situ annealing of the amorphous X-containing ferromagnetic alloy, the Heusler alloy pinned layer is deposited on the amorphous X-containing ferromagnetic layer and a second high-temperature annealing step is performed to improve the microstructure of the Heusler alloy pinned layer.

Abstract: An electrical lapping guide (ELG) for the fabrication of an air-bearing slider used in a magnetic recording disk drive is formed of a different material than the magnetoresistive (MR) read head or sensor so as to have both a high electrical resistivity and a substantially higher etch rate. When the ELG and MR sensor are etched simultaneously to form their respective back edges, the ELG will have a sharp well-defined non-tapered wall at the back edge. The ELG has a film thickness close to but generally thinner than that of the MR sensor, and a sheet resistance to generally match the resistance measurement capability of the lapping tool. The preferred material for the ELG is an alloy comprising silver (Ag) and one or more of Sn, Ge and zinc Zn.