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 in a write gap between a main pole (MP) trailing side and trailing shield (TS). The SHE layer contacts either the MP or TS, and has a front side at the air bearing surface or recessed therefrom. In one embodiment, a current (I1) is applied between the MP trailing side and SHE layer and is spin polarized to generate a first spin transfer torque that tilts a local MP magnetization to a direction that enhances a MP write field. In a second embodiment, a current (I2) is applied between the SHE layer and TS and is spin polarized to generate a second spin transfer torque that tilts a local TS magnetization to a direction that increases the TS return field and improves bit error rate.

Abstract: A spin transfer torque reversal assisted magnetic recording (STRAMR) structure is disclosed wherein two flux change layers (FCL1 and FCL2) are formed within a write gap (WG) and between a main pole (MP) trailing side and trailing shield (TS). Each FCL has a magnetization that flips to a direction substantially opposing a WG field when a direct current of sufficient current density is applied across the STRAMR device thereby increasing reluctance in the WG and producing a larger write field output at the air bearing surface. A reference layer (RL1) is used to reflect spin polarized electrons that exert spin torque on FCL1 and cause FCL1 magnetization to flip. A second reference layer (or the MP or TS) is employed to reflect spin polarize electrons that generate spin torque on FCL2 and flip FCL2 magnetization. Non-spin polarization preserving layers and spin polarization preserving layers are also in the STRAMR structure.

Abstract: An optically shielded (thermally assisted magnetic recording (TAMR) head comprises a perpendicular magnetic recording (PMR) write head and a near-field transducer (NFT) having an emerging peg at the air-bearing surface (ABS). Self-aligned optical side shields (SA-OSS) are formed using a self-aligning process that positions the shields symmetrically relative to the emergent peg of the NFT. As a result of the symmetric positioning the down-track and cross-track near-field and near-field gradients are significantly sharpened.

Abstract: A junction shield (JS) structure is disclosed for providing longitudinal bias to a free layer (FL) having a width (FLW) and magnetization in a cross-track direction between sidewalls in a sensor. The sensor is formed between bottom and top shields and has sidewalls extending from a front side at an air bearing surface (ABS) to a backside that is a stripe height (SH) from the ABS. The JS structure has a single layer (JS1) adjacent to each sensor sidewall and with a magnetization parallel to that of the FL, and a tapered top surface such that JS1 has decreasing thickness with increasing height from the ABS. As aspect ratio or AR (SH/FLW) increases above 1, longitudinal bias increases proportionally to slow an increase in asymmetry as AR increases, and without introducing a loss in amplitude for a reader with low AR.

Abstract: A preamplifier has a pre-compensation circuit that optimizes the write current in a low current range of less than 30 mA. The pre-compensation circuit maintains the peak current with a high overshoot current amplitude for achieving an optimized areal density capability to equalize the erase widths for the bit lengths of the encoded data with bit lengths greater than three clock time periods with encoded data with a bit length of the two clock time period. Alternately, the pre-compensation circuit has an overshoot generator that determines the optimum amplitude of the overshoot current for the bit-lengths for the encoded data. An overshoot data synchronizer is connected to a read current preamplifier to receive a pseudorandom read data signal that is applied to the overshoot generator to enable the different overshoot current amplitude depending on the bit length of the encoded data. The pre-compensated data current is transferred to the write head.

Abstract: A junction shield (JS) structure and method of forming the same are disclosed for providing longitudinal bias to a free layer (FL) having a width (FLW) and magnetization in a cross-track direction between sidewalls in a sensor. The sensor is formed between bottom and top shields and has sidewalls extending from a front side at an air bearing surface (ABS) to a backside at a stripe height (SH) from the ABS. The JS structure has a lower layer (JS1) with magnetization parallel to that of the FL, and a tapered top surface such that JS1 has decreasing thickness with increasing height from the ABS. As aspect ratio or AR (SH/FLW) increases above 1, longitudinal bias increases proportionally to slow an increase in asymmetry as AR increases, and without decreasing amplitude for a reader with low AR. The JS1 layer may be antiferromagnetically coupled to an upper JS layer for stabilization.

Abstract: A magnetic tunnel junction (MTJ) is disclosed wherein a nitride diffusion barrier (NDB) has a L2/L1/NL or NL/L1/L2 configuration wherein NL is a metal nitride or metal oxynitride layer, L2 blocks oxygen diffusion from an adjoining Hk enhancing layer, and L1 prevents nitrogen diffusion from NL to the free layer (FL) thereby enhancing magnetoresistive ratio and FL thermal stability, and minimizing resistance x area product for the MTJ. NL is the uppermost layer in a bottom spin valve configuration, or is formed on a seed layer in a top spin valve configuration such that L2 and L1 are always between NL and the FL or pinned layer, respectively. In other embodiments, one or both of L1 and L2 are partially oxidized. Moreover, either L2 or L1 may be omitted when the other of L1 and L2 is partially oxidized. A spacer between the FL and L2 is optional.

Abstract: A method of forming a spin torque assisted magnetic recording writer is disclosed wherein a spin flipping (STO) device is recessed from an air bearing surface. The STO device has a middle flux guiding layer with a magnetization that flips to a direction anti-parallel to the write gap field when a current of sufficient magnitude is applied from the trailing shield towards the main pole (MP) thereby increasing reluctance in the write gap to enhance writability. A STO stack is deposited and patterned to define a cross-track width on the MP tapered trailing side. Thereafter, the STO stack is patterned to define a STO device with a front side recessed from the air bearing surface, and a backside. A write gap is deposited surrounding the STO device, and has a thickness greater than or ? to STO thickness to enable design flexibility. Then, first and second trailing shields are formed.

Abstract: An MTJ or MR read sensor is formed by depositing a stack in a reverse order with a free layer (FL) deposited on a lower shield, followed by a tunneling barrier layer (for an MTJ) or a conducting spacer layer (for an MR) and, finally, an antiferromagnetically coupled pinning structure and an upper shield. This reverse order permits a series of etching processes to be accurately performed on the lower shield and the stack together with the formation of biasing layers that are coupled to the lower shield and the stack, without adversely affecting the stability of the pinning structure. Further, the distance between the FL and the shield is accurately determined and repeatable even down to the sub-nm regime. An upper shield can then be formed and also coupled to the biasing layers.

Abstract: The use of supermalloy-like materials such as NiFeMe where Me is one or more of Mo, Cr, and Cu for the side and top shields of a magnetic bit sensor is shown to provide better shielding protection from stray fields because of their extremely high permeability. Moreover, the side shield may comprise a stack in which a Ni, Fe, Co, FeNi, CoFe, or FeCo is sandwiched between two NiFeMe layers to enhance the bias field on an adjacent free layer. Including NiFeMe in a side shield results in an increase in readback amplitude under the same asymmetric sigma. For these sensors, the signal to noise ratio was higher and the bit error rate was lower than with conventional materials in the side shield. A method is disclosed for forming a magnetic bit sensor having supermalloy-like materials in the side shields.

Abstract: A thermally assisted magnetic head including a slider and a light source-unit. The slider includes a slider substrate and a magnetic head part. The light source-unit includes a laser diode and a sub-mount. The magnetic head part includes a medium-opposing surface, a light source-opposing surface and a waveguide which guides laser light from the light source-opposing surface to the medium-opposing surface. The slider substrate includes a light source-cavity formed in a light source-placing surface on which the light source-unit is placed. The light source-cavity includes an opening concave part being formed larger than a mount bottom surface of the sub-mount. The mount bottom surface of the sub-mount is inserted into the opening concave part to be joined to the light source-cavity.

Abstract: A spin transfer torque reversal assisted magnetic recording (STRAMR) device is disclosed wherein a flux guiding layer (FGL) magnetization flips to an opposite direction opposing the write gap (WG) field because of spin torque from an adjacent spin polarization (SP) layer and spin injection layer (SIL) when a current (Ia) of sufficient density is applied across the device and between the main pole (MP) and trailing shield (TS) thereby enhancing the MP write field. The SP layer adjoins the MP or TS and maintains a magnetization in the WG field direction. One or both of the SIL and FGL has a spin polarization from ?0.4 to 0.3 and may be doped with C, N, or B so that the extent of FGL flipping is greater at a given current density than in the prior art where all magnetic layers within the STRAMR device have a positive spin polarization ?0.4.

Abstract: A write head configured for thermally assisted magnetic recording (TAMR) has a split-yoke design that allows the yoke and magnetic pole to be formed as planar layers while the split between left and right-side portions of the yoke and magnetic pole eliminate adverse coupling between the magnetic writing field and the optical near-field heating field. The planar design is easy to fabricate and provides rapid rise time and a strong magnetic field using fewer current-carrying coils than in the prior art.

Abstract: A PMR writer with a true one turn design is disclosed with a driving coil above the main pole (MP) but where a bucking coil below the MP is replaced by a dummy metal layer or fully removed to substantially enhance the return field to the trailing shield. A non-double write shield scheme is employed where the leading loop for magnetic flux return is terminated at the leading shield. A tapered bottom yoke (tBY) contacts the MP bottom surface and has a tapered front side at height tBYd from the air bearing surface. Bottom yoke (BY) is below the tBY and has a front side at height BYd where BYd>tBYd. Reader-writer separation is reduced by 1-2 microns when the bucking coil is fully removed. Wide adjacent track erasures are controlled with a high damping material in one or more of the leading, side and trailing shields.

Abstract: A near field transducer (NFT) is formed between a waveguide and main pole at an air bearing surface (ABS). The NFT includes a rod-like front portion (PG1) and a substantially triangular shaped back portion (PG2) with a dielectric separation layer therebetween. PG1 is formed on a first dielectric layer with thickness t1 and refractive index (RI1) while PG2 is on a second dielectric layer with thickness t2 and having refractive index (RI2) where t1>t2, and RI1>RI2 while PG1 has a tapered backside at angle 45+15 degrees to promote efficient energy transfer from PG2 to PG1 and reduce NFT heating. A dielectric layer that induces poor adhesion with PG1 may be inserted between below PG1 at the ABS to cause Au recession to occur at the PG1 leading side thereby preventing voids at the PG1 trailing side and ensuring good ADC performance.

Abstract: A magnetic head includes a coil, a main pole, a write shield, a lower return path section, and an accommodation section. The accommodation section accommodates at least part of the return path section. A first portion of the accommodation section has a first inclined surface. A second portion of the accommodation section has a second inclined surface. A coil element of the coil has a third inclined surface opposed to the first inclined surface, and a fourth inclined surface opposed to the second inclined surface. The lower return path section includes a first inclined portion extending along the first inclined surface, and a second inclined portion extending along the second inclined surface.

Abstract: A spin transfer torque reversal assisted magnetic recording (STRAMR) device is disclosed wherein a flux change layer (FCL) is formed between a main pole (MP) trailing side and a trailing shield (TS). The FCL has a magnetization that flips to a direction substantially opposing the write gap magnetic field when a direct current (DC) of sufficient current density is applied across the STRAMR device thereby increasing reluctance in the WG and producing a larger write field output at the air bearing surface. Heat transfer in the STRAMR device is enhanced and production cost is reduced by enlarging the STRAMR width to be essentially equal to that of the TS, and where the TS and STRAMR widths are formed using the same process steps. Bias voltage is used to control the extent of FCL flipping to a center portion to optimize the gain in area density capability in the recording system.

Abstract: A PMR (perpendicular magnetic recording) write head configured for microwave assisted magnetic recording (MAMR) includes a spin-torque oscillator (STO) and trailing shield formed of high moment magnetic material (HMTS). By patterning the STO and the HMTS in a simultaneous process the HMTS and the STO layer are precisely aligned and have very similar cross-track widths. In addition, the write gap at an off-center location has a thickness that is independent from its center-track thickness and the write gap total width can have a flexible range whose minimum value is the same width as the STO width.

Abstract: A magnetic head includes a medium facing surface, a coil, a main pole, and a substrate. The main pole includes a first layer, and a second layer lying on the first layer. The first layer includes a thickness-changing portion whose dimension in a direction perpendicular to a top surface of the substrate decreases with decreasing distance to the medium facing surface. At least part of the second layer is located on the thickness-changing portion.

Abstract: A method of operating an HDD having a slider-mounted read/write head that is configured for dynamic fly-height operation (DFH) and includes at least one head-disk interference sensor (HDIs). By operating the DFH to lower the head and subjecting the HDIs signal to a power-law enhancement, a consistent and accurate determination of the touchdown power (TDP) can be obtained. Combining absolute TDP determination with a method for measuring relative changes of FH, an absolute determination of FH can be determined.