Abstract: A PMR (perpendicular magnetic recording) head is configured for thermally assisted magnetic recording (TAMR). The thermal energy is supplied by the near-fields of plasmons and the near-fields are directed to a magnetic recording medium by a PPG layer. The PPG layer is Rhodium (Rh) whose small-grained crystal structure normally makes it subject to thermal deformations and other weaknesses. By growing the PPG layer on a thin template layer (TTL), the portion of the PPG layer adjacent to the air-bearing surface (ABS) develops a larger grain size and stronger forces between its atomic constituents which makes it resistant to those deformations.

Abstract: A Spin Hall Effect (SHE) assisted magnetic recording device is disclosed wherein a stack of two SHE layers with an intermediate insulation layer is formed between a main pole (MP) trailing side and trailing shield (TS) bottom surface. Both of the SHE layers are a Spin Hall Angle (SHA) material with an absolute value for SHA>0.05. The SHE layers have front sides at the air bearing surface (ABS) or recessed therefrom, and backsides up to 80 nm from the ABS. Current (ISHE) is applied in a cross-track direction and synchronized with the write current. A first SHE layer generates transverse spin transfer torque that tilts a local MP magnetization at the MP trailing side to enhance the MP write field, and the second SHE layer generates transverse spin transfer torque that tilts a local TS magnetization at the TS bottom surface to increase the TS return field.

Abstract: A Spin Hall Effect (SHE) assisted magnetic recording device is disclosed wherein a SHE layer comprising a giant Spin Hall Angle material is formed between a main pole (MP) trailing side and trailing shield (TS) bottom surface. The SHE layer may contact one or both of the MP and TS, has a front side at the air bearing surface (ABS) or recessed therefrom, and a backside up to 80 nm from the ABS. Current (ISHE) is applied in a cross-track direction and synchronized with the write current. Depending on SHE layer placement, a transverse spin transfer torque is applied to one or both of a local MP magnetization at the MP trailing side and a local TS magnetization at the TS bottom surface thereby tilting the former to a direction that enhances the MP write field and tilting the latter to a direction that increases the TS return field.

Abstract: A PMR writer is disclosed with an all wrap around (AWA) shield design in which one or more of the leading shield, lead edge taper (LET), and side shields are comprised of a low moment high damping (LMHD) magnetic material having a damping constant ?0.04 and a magnetic flux density (Bs) from 1 kilogauss (kG) to 8 kG. The LMHD magnetic material may be FeNiM, FeCoM, FeNM, or FeCoNiM where M is a 3d, 4d, or 5d transition metal. The LET layer has a tapered side adjoining the leading gap and with a thickness that decreases to zero at height h1 of 50 nm to 500 nm from the air bearing surface. The leading shield also has a backside at h1. Wide adjacent track erasure is minimized while area density capability is enhanced compared with conventional shields with Bs from 10-19 kG.

Abstract: A spin torque transfer (STT) assisted magnetic recording structure is disclosed wherein a magnetic flux guiding (MFG) device is formed between a main pole (MP) trailing side and a trailing shield (TS). The MFG device has a field generation layer (FGL) separated from first and second spin polarization (SP) layers by first and second non-magnetic layers, respectively. First and second SP layers have magnetizations in opposite directions so that when a direct current of sufficient magnitude is applied from the MP to TS, or from the TS to MP in other embodiments, FGL magnetization flips to a direction toward the MP and opposes a write gap field flux thereby enhancing the write field. Additive torque from two SP layers on the FGL enables lower current density for FGL flipping or a greater degree of FGL flipping at a given current density compared with MFG schemes having a single SP layer.

Abstract: A bottom shield in a read head is modified by including a non-magnetic decoupling layer and second magnetic layer on a conventional first magnetic layer. The second magnetic layer has a magnetization that is not exchange coupled to the first magnetic layer, and a domain structure that is not directly affected by stray fields due to domain wall motion in the first magnetic layer. Accordingly, the modified bottom shield reduces shield related noise on the reader and will provide improved signal to noise (SNR) ratio and better reader stability. The second magnetic layer may be further stabilized with one or both of an antiferromagnetic coupling scheme, and insertion of an antiferromagnetic pinning layer. In dual readers, the modified bottom shield is used in either the bottom or top reader although in the latter, first magnetic layer thickness is reduced to maintain reader-to-reader spacing and acceptable bit error rate (BER).

Abstract: A PMR writer is disclosed with a leading shield in which a lower (LS2) layer, a middle LS1 layer, and an upper leading edge taper (LET) layer have a damping parameter?0.04, and extend from an air bearing surface (ABS) to a first height (h1) from the ABS. The LS2 layer has a notch filled with dielectric material at the air bearing surface (ABS) that extends to a height?h1, or may be completely replaced with dielectric material. Two notch front sides each form an angle ? with the LS1 bottom surface, and two notch inner sides between the ABS and LS2 backside form angle ? with the ABS where each of ? and ? is from 10 degrees to 170 degrees. Accordingly, bits per square inch performance is improved while substantially maintaining tracks per square inch capability for an overall gain in area density capability.

Abstract: A method of forming a PMR writer with an all wrap around (AWA) shield design in which one or more of the leading shield, side shields, and trailing shield (TS) structure (except the hot seed layer) at the air bearing surface (ABS) are comprised of an alloy having a damping parameter ? of ?0.04 to minimize wide area track erasure (WATE). The TS structure comprises two outer magnetic layers with an 8-16 kiloGauss (kG) saturation magnetic moment (Ms) on each side of a center stack with a lower write gap, a middle hot seed layer (Ms of 19-24 kG), and an upper magnetic layer (Ms of 16-24 kG). The hot seed layer and upper TS magnetic layer promote improved area density capability (ADC). A second TS layer with Ms of 16-24 kG and a full width at the ABS may be formed on the upper magnetic layer.

Abstract: A spin torque transfer (STO) assisted magnetic recording structure is disclosed wherein a STO device has capability to generate a radio frequency (RF) field on a magnetic bit to lower the required write field during a write process. The STO device contains a field generation layer (FGL) with a magnetization that flips to a direction opposite to the write gap field when a current of sufficient current density is applied thereby increasing reluctance in the write gap and causing a larger write field output at the air bearing surface. A key feature is that a single spin polarization (SP) layer and an antiferromagnetically coupled SP layer comprised of SP1 and SP2 layers are formed on opposite sides of the FGL. SP1 magnetization is greater than SP2 magnetization. Additive torque from SP and SP2 layers on the FGL enables FGL flipping while SP1 and SP2 precessional states provide the RF field.

Abstract: A dual perpendicular magnetic recording writer is disclosed wherein the better of two writers on a slider is determined by performance testing, and is then integrated into a head gimbal assembly. Main pole layers in the two writers are separated by a cross-track width <10 microns to minimize read-write offset. Each of the driving coil (DC) and bucking coil (BC) have two outer portions forming a U shape with a front side, and each have a center portion connected to the front side proximate to an air bearing surface and a backend contacting an interconnect. A write current passes from a BC outer portion below the main pole in the selected writer through the BC center portion to the interconnect, and then through the DC center portion to a DC outer portion above the main pole in the selected writer. Area density capability mean and sigma are improved.

Abstract: A microwave assisted magnetic recording (MAMR) writer has a recessed spin flipping element formed in the write gap between the MP tapered trailing side and a first trailing shield, a thickness ? to the write gap thickness, and a width ? to a maximum width of the MP tapered trailing side. The spin flipping element has a lower non-spin preserving layer, a middle flux guiding layer (FGL), and an upper spin preserving layer. The FGL has a magnetization that flips to a direction substantially anti-parallel to the write gap field when a current of sufficient magnitude is applied from the trailing shield towards the MP thereby increasing reluctance in the write gap and forcing additional flux out of the MP at the air bearing surface to enhance writability and tracks per inch capability on a recording medium while maintaining bits per inch capability compared with conventional MAMR writers.

Abstract: A spin torque transfer (STT) assisted magnetic recording structure is disclosed wherein a magnetic flux guiding (MFG) device is formed between a main pole (MP) trailing side and a trailing shield (TS). The MFG device has a field generation layer (FGL) separated from first and second spin polarization (SP) layers by first and second non-magnetic layers, respectively. First and second SP layers have magnetizations in opposite directions so that when a direct current of sufficient magnitude is applied from the MP to TS, or from the TS to MP in other embodiments, FGL magnetization flips to a direction toward the MP and opposes a write gap field flux thereby enhancing the write field. Additive torque from two SP layers on the FGL enables lower current density for FGL flipping or a greater degree of FGL flipping at a given current density compared with MFG schemes having a single SP layer.

Abstract: A dual PMR writer is disclosed wherein a first main pole (MP1) in writer 1 is a mirror image of a second main pole (MP2) in writer 2 with respect to a center plane aligned orthogonal to the air bearing surface (ABS). MP1 and MP2 may have an asymmetrical top-down shape to reduce writer-writer spacing (WWS) and read write offset (RWO) when a single or double reader is positioned down-track at the center plane. Accordingly, there is less track misregistration and better area density capability. Each of MP1 and MP2 as well as a top yoke (TY), and a tapered bottom yoke (tBY) have a rectangular back portion of width “w” from 4 to 10 microns. Spacing between MP1 and MP2 back portions may be ?4 microns to prevent cross-talk. RWO is reduced from ?4 microns for symmetrical TY/MP/tBY shapes to 3 microns or less for asymmetrical shapes.

Abstract: A pad/trace line layout for a PMR writer structure having two or more writers on a slider, and a process for selecting the best of the multiple writers is disclosed. Each writer is individually probed with a spin stand test device to generate performance results including bit error rate (BER), and area density capability (ADC). After the best writer is determined, the slider is integrated in a HGA. Only the best writer is connected through trace lines to a preamp to enable functionality. At least one trace line has a plurality of arms that enable flexibility in connecting the best writer to the preamp while other arms are not connected. In some embodiments, all writers share a common W? pad that is connected to the preamp through one of two trace lines while the other trace line has one of the plurality of arms connected to the best writer.

Abstract: A dual perpendicular magnetic recording writer is disclosed wherein first and second dynamic fly height (DFH) heaters WDFH1 and WDFH2, are formed in first and second writers, respectively, on a slider in a head gimbal assembly. In one embodiment, WDFH1 and WDFH2 have front sides that are recessed behind first and second back gap connections (BGC), respectively, and join together at their respective backsides behind the interconnect which connects a bucking coil and driving coil each symmetrically disposed about a center plane separating the two writers. In another embodiment with a separate bucking coil in each writer, WDFH1 and WDFH2 are formed behind separate interconnects. Magnetic spacing loss is reduced compared with a single DFH heater spread across both writers. Close point at touchdown in a cross-track direction and the size of the touchdown area are controlled by applying a WDFH1:WDFH2 power ratio from 100:0 to 0:100.

Abstract: A seed layer stack with a smooth top surface having a peak to peak film thickness variation of about 0.5 nm is formed by sputter depositing a second seed layer on a first seed layer that is Mg, MgN, or an alloy thereof where the second seed layer has a bond energy substantially greater than that of the first seed layer. The second seed layer may be Ta or NiCr. In some embodiments, an uppermost seed layer that is one or both of Ru and Cu is deposited on the second seed layer. Higher coercivity (Hc) and perpendicular magnetic anisotropy (Hk) is observed in an overlying ferromagnetic layer than when a prior art seed layer stack is employed. The first seed layer has a thickness from 2 to 20 Angstroms and has a resputtering rate about 2 to 40 times that of the second seed layer.

Abstract: A method is disclosed for forming a perpendicular magnetic recording writer with an all wrap around (AWA) shield design wherein one or more of the leading shield, trailing shield, and side shields are a composite wherein a magnetic “hot seed” layer made of a >19 kG to 24 kG material adjoins a gap layer, and a side of the hot seed layer opposite the gap layer adjoins a high damping magnetic layer made of a 10-16 kG material (or a 16-19 kG material in the trailing shield) having a Gilbert damping parameter ?>0.04. In one embodiment, the high damping magnetic layer is FeNiRe with a Re content of 3 to 15 atomic %. The main pole leading and trailing sides may be tapered. Side shields may have a single taper or dual taper structure. Higher writer speed with greater areal density capability is achieved.

Abstract: A perpendicular magnetic recording writer is disclosed wherein a first trailing shield (HMTS) layer has a down-track (DT) thickness d in portions thereof proximate to a center plane that bisects the main pole tip trailing side to enable enhanced trailing shield return field at track center thereby improving bits per inch (BPI) capability. Meanwhile, at off track center positions, that in some embodiments are from 25 nm to 500 nm from the center plane, the HMTS layer has a DT thickness d1, where d1>d, and a smaller dielectric gap between the HMTS layer and the main pole thereby protecting side shield return field and adjacent track interference (ATI) performance. A method of forming the HMTS layer on a write gap is provided and includes patterning the HMTS layer in a back portion to form openings that are filled with the smaller dielectric gap and HTMS layer thickness d1.

Abstract: A TAMR (thermally assisted magnetic recording) write head uses a gap-based NFT (near-field transducer) to create plasmon near field energy. In one embodiment the NFT is a double ridge aperture structure that simultaneously delivers low transition curvature and better cross-track thermal gradients than previous designs. In another embodiment a NFT comprises a top and bottom ridge not confined to an aperture structure, made of thermo-mechanically stable materials and a parabolic shaped metal layer disposed adjacent to a dielectric waveguide core to couple optical energy to surface plasmon modes.

Abstract: A perpendicular magnetic recording writer has a main pole (MP) with a write gap formed between the MP trailing side and a trailing shield, a side gap between each MP side and a side shield, and a leading gap between the MP leading side and a leading shield. A flux guiding element is formed in at least one gap and comprises an inner non-spin preserving layer adjoining the MP, a middle flux guiding layer (FGL), and an outer spin preserving layer. A key feature is that the FGL has a magnetization that may be aligned anti-parallel to a gap field during a write process when a current of sufficient magnitude is applied from the adjacent shield towards the MP thereby increasing reluctance in the gap and forcing additional flux out of the MP at the air bearing surface to enhance writability on a magnetic recording medium.