Abstract: A method for manufacturing a magnetic write head that has a trailing magnetic shield with a tapered write pole trailing edge, a non-magnetic step layer and a Ru bump and an alumina bump formed at the front of the non-magnetic step layer. The process forms a Ru/alumina side wall at the sides of the write pole, such that the Ru side wall is closest to the write pole. The Ru is removed more readily than the alumina during the ion milling that is performed to taper the write pole. This causes the Ru portion of the side wall to taper away from the write pole rather than forming an abrupt step. This tapering prevents dishing of the trailing edge of the write pole for improved write head performance.

Abstract: A magnetic structure in one embodiment includes a tunnel barrier layer; a free layer; and a buffer layer between the tunnel barrier layer and the free layer, wherein a cross sectional area of the tunnel barrier layer in a direction parallel to a plane of deposition thereof is greater than a cross sectional area of the free layer in a direction parallel to a plane of deposition thereof, wherein a cross sectional area of the buffer layer in a direction parallel to a plane of deposition thereof is greater than a cross sectional area of the free layer in the direction parallel to the plane of deposition thereof. Additional systems and methods are also presented.

Abstract: A method and a storage system are provided for implementing deterministic memory allocation for indirection tables for persistent media or disk drives, such as, shingled perpendicular magnetic recording (SMR) indirection tables. A plurality of fixed-size memory pools are used to store indirection data. The distribution of pool allocate sizes is fixed. A pool allocate size is selected based upon an indirection system request size.

Abstract: A method and a storage system are provided for implementing indirection tables and providing enhanced updates of the indirection tables for persistent media or disk drives, such as shingled perpendicular magnetic recording (SMR) indirection tables. A plurality of memory pools are used to store indirection data. An exception pointer table provides a pointer to an exception list for an I-Track. The exception list includes predetermined-size exception entries sorted by an offset from a start of the I-Track. An insert exception entry is provided for a new host write and merged to an updated exception list using an offset of the insert exception entry.

Abstract: A magnetic head for data recording having a pair of heating elements that self regulate in response to temperature to distribute heat for thermal actuation. The head includes a first heating element located adjacent to the read sensor and away from the writer, and a second heating element located adjacent to the writer. The first and second heating elements have different coefficients of thermal resistance that cause the heating of the second heating element to increase relative to that of the first heating element when the overall temperature increases or when power provided by a power source increases. There, thereby prevents the read sensor from extending too much and possibly contacting the disk.

Abstract: The invention provides a TMR read sensor with low-contact-resistance metal/metal, metal/oxide and oxide/metal interfaces. The low-contact-resistance metal/metal interfaces in a reference or sense layer structure are in-situ formed in a high-vacuum deposition module of a sputtering system, without exposures to low vacuum in a transfer module and damages caused by a plasma treatment conducted in an etching module. The low-contact-resistance metal/oxide interface is formed by utilizing a thin Co—Fe—B reference layer and a thick Co—Fe reference layer to reduce boron diffusion and segregation caused by annealing. The low-contact-resistance oxide/metal interface is formed by replacing a Co—Fe—B sense layer with a Co-rich Co—Fe sense layer to eliminate boron diffusion and segregation caused by annealing. With the low-contact-resistance metal/metal, metal/oxide and oxide/metal interfaces, the TMR read sensor exhibits a junction resistance-area product of below 0.

Abstract: A method and a storage system are provided for implementing indirection tables for persistent media or disk drives with enhanced emergency power outage (EPO) protection for the indirection data, such as shingled perpendicular magnetic recording (SMR) indirection tables. Chaining of indirection data is provided with one block pointing to another block of the indirection data stored to disk or flash memory. An EPO-safe buffer is used to store a metadata entry responsive to completing each host write command. Each metadata entry is added to a metadata block, a pointer is stored in the EPO-safe buffer to a current metadata block and a previous metadata block. For a next EPO-safe buffer update entries are removed for the previous metadata block, keeping the last two metadata pointers and last metadata block.

Abstract: A method for predicting and optimizing magnetic core width of a write head using neural networks to analyze manufacturing parameters, and determining new manufacturing parameters that will provide more optimal magnetic core width results. The manufacturing parameters can include: write pole flare point; wrap around shield dimension; and side gap dimension.

Abstract: A disk drive. The disk drive includes: a head for accessing a data recording area of a disk; an actuator for pivoting to move the head; a voice coil motor; and, a latch configured to lock the actuator from pivoting toward the data recording area in response to an external force. The voice-coil motor includes a voice coil, a magnet, and a yoke. The latch is positioned at a closed position when the actuator is positioned at a stand-by position, and is configured to pivot by application of a magnetic bias force with pivoting of the actuator from the stand-by position into proximity with the data recording area such that the latch is configured to stop at an open position. The yoke includes a protrusion which protrudes toward the magnetic body at the open position.

Abstract: According to one embodiment, a perpendicular magnetic recording head includes a main pole, wherein a thickness in a down-track direction of the main pole increases moving away from an air bearing surface of the magnetic pole, and wherein a center position in a thickness direction of a portion of the main pole which is exposed at the air bearing surface (the ABS portion) is positioned toward a trailing side of the main pole with respect to a center position in a thickness direction of a portion of the magnetic pole having a greatest cross-sectional area and which is set back from the air bearing surface (the set-back portion). Further embodiments of this magnetic recording head, along with systems thereof and methods of producing magnetic recording heads are also described, according to more embodiments.

Abstract: Embodiments of the present invention pertain to sealing an enclosure for a disk drive form factor. According to one embodiment, material is removed from a base casting for the disk drive form factor to enable insertion of a component. The removal of the material results in a portion of the base casting being thin enough to potentially cause an inadvertent hole in the base casting. A hole is purpose created in the base casting to avoid development of the inadvertent hole. A seal is used to cover the created hole in a manner that allows for insertion of the component.

Abstract: A patterned perpendicular magnetic recording medium has discrete data islands that have first and second ferromagnetic layers (MAG1 and MAG2) with first and second nonmagnetic interlayers (IL1 and IL2) between MAG1 and MAG2. MAG1 and MAG2 may be similar CoPtCr alloys with similar thicknesses, with thicknesses of IL1 and IL2 that assure that MAG1 and MAG2 are strongly exchange coupled. Alternatively, MAG2 may be a “write assist” layer, for example a high-saturation magnetization, magnetically soft material in an exchange-spring structure, with IL1 being very thin so that IL2 functions as the coupling layer between MAG1 and the write-assist MAG2 layer. In an application for thermally-assisted recording (TAR), MAG2 may be the chemically-ordered equiatomic binary alloy FePt or CoPt based on the L10 phase, with high magneto-crystalline anisotropy (Ku).

Abstract: A method for manufacturing a magnetic write head having a write pole with a tapered leading edge and a tapered trailing edge. The method includes forming a non-magnetic bump player over a surface, forming a mask over the non-magnetic bump layer and performing a first ion milling to form a tapered back edge on the non-magnetic bump layer. A magnetic write pole material is then deposited over the surface and over the non-magnetic bump layer. Then a non-magnetic step structure is formed over the magnetic write pole material and an ion milling is performed to form a taper on the upper surface of the write pole. The write pole lateral dimensions can then be defined, and a non-magnetic bump formed over the tapered portion of the upper surface of the write pole. Another ion milling can then be performed to extend the taper of the surface of the write pole.

Abstract: A spin-torque oscillator (STO) has a single free ferromagnetic layer that forms part of both a giant magnetoresistance (GMR) structure with a nonmagnetic conductive spacer layer and a tunneling magnetoresistance (TMR) structure with a tunnel barrier layer. The STO has three electrical terminals that connect to electrical circuitry that provides a spin-torque excitation current through the conductive spacer layer and a lesser sense current through the tunnel barrier layer. When the STO is used as a magnetic field sensor, the excitation current causes the magnetization of the free layer to oscillate at a fixed base frequency in the absence of an external magnetic field. A detector coupled to the sense current detects shifts in the free layer magnetization oscillation frequency from the base frequency in response to external magnetic fields.

Abstract: A perpendicular magnetic recording write head has an improved antiparallel-coupled laminated main pole (MP) with a tapered trailing edge. The laminated MP has three ferromagnetic layers and two non-magnetic antiparallel-coupling (APC) layers. A first ferromagnetic layer (FM1) has a thickness T1 and a planar end face at the air-bearing surface (ABS). A second ferromagnetic layer (FM2) has a total thickness T2 and includes a first portion with a thickness T4 that has an end face coplanar with the end face of FM1 and a second portion with a tapered end face. A first APC layer separates FM1 and FM2. A third ferromagnetic layer (FM3) has a thickness T3 and a tapered end face that is coplanar with the tapered end face of FM2. A second APC layer separates FM2 and FM3. The net flux is minimized at both the ABS and at MP cross-sections recessed from the ABS.

Abstract: A data storage device encrypts data stored in non-volatile memory using a bulk encryption key. The data storage device uses a key derivation function to generate an initial encryption key. The data storage device then wraps an intermediate encryption key with the initial encryption key and stores the wrapped intermediate key in the non-volatile memory. The data storage device wraps the bulk encryption key with the intermediate encryption key and stores the wrapped bulk encryption key in the non-volatile memory. The data storage device can unwrap the wrapped intermediate key to generate the intermediate encryption key using the initial encryption key. The data storage device can unwrap the wrapped bulk encryption key to generate the bulk encryption key using the intermediate encryption key. The data storage device decrypts data stored in the non-volatile memory using the bulk encryption key.

Abstract: A method for changing resonance frequency of hard disk drive components to reduce electromagnetic interference and electrostatic discharge from said components. Electrically sensitive hard disk drive components having a high resonance frequency consistent with a resonance of present electromagnetic interference forces are determined. A damper material is layered to alter electrical properties of said hard disk drive components to limit the magnitude of electromagnetic interference potential of said electrically sensitive component. Electrically sensitive hard disk drive components having a high capacitance are determined. The damper material is layered to increase a volume of the material constitution of the hard disk drive components to alter a capacitance of the hard disk drive component.

Abstract: In one embodiment, a magnetic head slider includes a substrate, at least two elements (read element, write element, and/or heater element) positioned adjacent to the substrate, a resistance detection element positioned near the two elements, a pair of conductive terminals in an accessible position and coupled to each of the two elements, a protective film surrounding the two elements and the resistance detection element, a first and a second thin conductive wire extending from the resistance detection clement and terminating at an edge of the protective film, a third thin conductive wire extending from one of the pair of conductive terminals for a first of the two elements and terminating at an edge of the protective film, and a fourth thin conductive wire extending from one of the pair of conductive terminals for a second of the two elements and terminating at an edge of the protective film.

Abstract: Techniques for securing data stored on a data storage device are provided. The data storage device encrypts the data using a bulk encryption key and stores the bulk encryption key in non-volatile memory in an encrypted format. The data storage device generates a challenge and response pair, wraps a secret key with the response to generate a wrapped secret key, and stores the challenge and the wrapped secret key in the non-volatile memory. The data storage device authenticates a host by reading the challenge and the wrapped secret key from the non-volatile memory, erasing the challenge and the wrapped secret key from the non-volatile memory, sending the challenge to the host, receiving the response from the host, and unwrapping the wrapped secret key using the response from the host to regenerate the secret key.

Abstract: In one embodiment, a system includes a writer for shingled recording which includes a write pole having a trailing edge and first and second side edges extending from the trailing edge. The writer further includes a shield extending along and about parallel to only a portion of the trailing edge or only a portion of the first side edge, and the shield does not extend along the second side edge. In addition, an angle formed between the first side edge and the trailing edge along an air bearing surface side of the writer is different than an angle formed between the second side edge and the trailing edge along the air bearing surface side of the writer. Other systems are also presented which include advanced shingled writing head designs.