Abstract: A magnetic recording medium 1 includes a substrate 11; and a metallic glassy layer 12 that is arranged on the substrate 11 and has a plurality of convex portions 12A and concave portions 12B. The metallic glassy layer 12 has a chemical composition represented by any one of the formulae (1) to (3): FemPtnSixByPz (wherein, 20<m?60 at %, 20<n?55 at %, 11?x<19 at %, 0?y<8 at %, and 0<z<8 at %)??(1); Fe55Pt25(SixByPz)20 (wherein, 11?x<19 at %, 0?y<8 at %, and0 <z<8 at %)??(2); and (Fe0.55Pt0.25Si0.16B0.02P0.02)100-xMx (wherein, 0<X?6 at %; and M represents an element or a combination of any two or more of the elements selected from Zr, Nb, Ta, Hf, Ti, Mo, W, V, Cr, Mn, Al, Y, Ag,and rare earth elements.)??(3).
Abstract: A plasmon-generator of the invention is configured to include a first configuration member including a near-field light generating end surface; and a second configuration member joined and integrated with the first configuration member and not including the near-field light generating end surface. The first configuration member is configured to contain Au as a primary component and to contain any one or more elements selected from a group of Co, Fe, Sb, Nb, Zr, Ti, Hf, and Ta, and is configured so that a content percentage X1 of the contained element is within a range between 0.2 at % or more and 2.0 at % or less. Thereby, thermostability, optical characteristic, and the process stability are satisfied. Also, heat dissipation and heat generation suppression effect are extremely superior.
Abstract: A perpendicular magnetic recording medium adapted for high recording density and high data recording rate comprises a non-magnetic substrate having at least one surface with a layer stack formed thereon, the layer stack including a perpendicular recording layer containing a plurality of columnar-shaped magnetic grains extending perpendicularly to the substrate surface for a length, with a first end distal the surface and a second end proximal the surface, wherein each of the magnetic grains has: (1) a gradient of perpendicular magnetic anisotropy field Hk extending along its length between the first end and second ends; and (2) predetermined local exchange coupling strengths along the length.
Type:
Grant
Filed:
August 6, 2013
Date of Patent:
February 24, 2015
Assignee:
Seagate Technology LLC
Inventors:
Shaoping Li, Kaizhong Gao, Lei Wang, Wenzhong Zhu, Xiaobin Wang
Abstract: A substrate for a magnetic recording medium having a disc shape with a central hole is provided in which the surface roughness of the principal surface of the substrate is 1 angstrom or less in terms of root mean square roughness (Rq) when a space period (L) of an undulation in the circumferential direction is in the range 10 to 1,000 ?m, and in which when a component in the vertical axis direction of a line segment Z connecting a point A with the space period (L) of 10 ?m and a point B with the space period (L) of 1,000 ?m in a curve S marked on a double logarithmic graph which is obtained by analyzing the surface roughness using a spectrum and in which the horizontal axis is set to the space period (L) (?m) and the vertical axis is set to the power spectrum density (PSD) (k·angstrom2·?m) (where k is a constant) is defined as H and a displacement at which the component in the vertical axis direction of the curve S is the maximum with respect to the line segment Z is defined as ?H, a value (P) expressed by (?
Type:
Grant
Filed:
November 28, 2012
Date of Patent:
February 10, 2015
Assignee:
Showa Denko K.K.
Inventors:
Koji Yukimatsu, Yukihisa Matsumura, Yoshihito Sueoka, Junichi Kishimoto
Abstract: The invention provides a tunneling magnetoresistance (TMR) read sensor with a long diffusion path and ex-situ interfaces in a sense layer structure. The sense layer structure comprises a first sense layer preferably formed of a ferromagnetic Co—Fe film, a second sense layer preferably formed of a ferromagnetic Co—Fe—B film, and a third sense layer preferably formed of a ferromagnetic Ni—Fe film. The sense layer structure has a long diffusion path (defined as a total thickness of the first and second sense layers) and ex-situ interfaces for suppressing unwanted diffusions of Ni atoms. Alternatively, the sense layer structure comprises a first sense layer preferably formed of a ferromagnetic Co—Fe film, a second sense layer preferably formed of a ferromagnetic Co—Fe—B film, a third sense layer preferably formed of a ferromagnetic Co—Fe—B—Hf film, and a fourth sense layer preferably formed of a ferromagnetic Ni—Fe film.
Abstract: A device that includes a near field transducer (NFT); at least one cladding layer adjacent the NFT; and a discontinuous metal layer positioned between the NFT and the at least one cladding layer.
Type:
Grant
Filed:
June 29, 2012
Date of Patent:
February 3, 2015
Assignee:
Seagate Technology LLC
Inventors:
Tong Zhao, Michael Christopher Kautzky, Michael Allen Seigler, Yongjun Zhao, Jay Jayashankar, Xiaoyue Huang
Abstract: Disclosed is a method for manufacturing a substrate provided with a surface portion having a plurality of concave and convex configurations. The method includes a step of applying a solution between a mold having a configuration corresponding to the concave and convex configurations, and a substrate base member, the solution obtained by dissolving a constructional material for composing the surface portion in a solvent; a step of forming the surface portion by drying the solvent in a state that the solution is applied between the mold and the substrate base member; and a step of releasing the mold from the surface portion. The mold satisfies requirements that a contact angle of a contact portion of the mold to be contacted with the solution is smaller than 90° with respect to the solvent, and that a work of adhesion between the contact portion and the constructional material is smaller than a work of adhesion between the contact portion and the solvent.
Abstract: A CoFeB or CoFeNiB magnetic layer wherein the boron content is 25 to 40 atomic % and with a thickness <20 Angstroms is used to achieve high perpendicular magnetic anisotropy and enhanced thermal stability in magnetic devices. A dusting layer made of Co, Ni, Fe or alloy thereof is added to top and bottom surfaces of the CoFeB layer to increase magnetoresistance as well as improve Hc and Hk. Another embodiment includes a non-magnetic metal insertion in the CoFeB free layer. The CoFeB layer with elevated B content may be incorporated as a free layer, dipole layer, or reference layer in STT-MRAM memory elements or in spintronic devices including a spin transfer oscillator. Thermal stability is increased such that substantial Hk is retained after annealing to at least 400° C. for 1 hour. Ku enhancement is achieved and the retention time of a memory cell for STT-MRAM designs is increased.
Abstract: A storage element including: a storage layer; a magnetization fixed layer; and an insulating layer, wherein by injecting spin-polarized electrons in a laminating direction of a layered structure that includes the storage layer, the insulating layer, and the magnetization fixed layer, the orientation of magnetization of the storage layer changes and recording of information is performed on the storage layer, and an Fe film and a film that includes Ni are formed in order from an interface side that is in contact with the insulating layer, and a graded composition distribution of Ni and Fe is formed after heating on at least one of the storage layer and the magnetization fixed layer.
Abstract: A perpendicular magnetic recording (PMR) media structure with multiple exchange couple composite (ECC) layer structure is described. The PMR disk structure may include multiple soft magnetic layers with intervening hard magnetic layers and in between. The interface between the soft magnetic layers and the hard magnetic layers may be separated by exchange coupled layers.
Abstract: A substrate for suspension comprises a metallic substrate, an insulating layer formed on the metallic substrate, a conductor layer formed on the insulating layer, and a cover layer covering the conductor layer. The insulating layer and the cover layer are formed from different materials, whose coefficients of hygroscopic expansion are in the range between 3×10?6/% RH and 30×10?6/% RH. The difference between the coefficients of hygroscopic expansion of the two materials is 5×10?6/% RH or less.
Abstract: Perpendicular magnetic anisotropy and Hc are enhanced in magnetic devices with a Ta/M1/M2 seed layer where M1 is preferably Ti, and M2 is preferably Cu, and including an overlying (Co/Ni)X multilayer (x is 5 to 50) that is deposited with ultra high Ar pressure of >100 sccm to minimize impinging energy that could damage (Co/Ni)X interfaces. In one embodiment, the seed layer is subjected to one or both of a low power plasma treatment and natural oxidation process to form a more uniform interface with the (Co/Ni)X multilayer. Furthermore, an oxygen surfactant layer may be formed at one or more interfaces between adjoining (Co/Ni)X layers in the multilayer stack. Annealing at temperatures between 180° C. and 400° C. also increases Hc but the upper limit depends on whether the magnetic device is MAMR, MRAM, a hard bias structure, or a perpendicular magnetic medium.
Abstract: A magnetoresistive element according to an embodiment includes: a base layer; a first magnetic layer formed on the base layer and having a changeable magnetization direction with an easy axis of magnetization in a direction perpendicular to a film plane; a first nonmagnetic layer formed on the first magnetic layer; and a second magnetic layer formed on the first nonmagnetic layer and having a fixed magnetization layer with an easy axis of magnetization in a direction perpendicular to the film plane. The first magnetic layer includes a ferrimagnetic layer having a DO22 structure or an L10 structure, the ferrimagnetic layer has a c-axis oriented in a direction perpendicular to the film plane, and the magnetization direction of the first magnetic layer is changeable by a current flowing through the first magnetic layer, the first nonmagnetic layer, and the second magnetic layer.
Type:
Grant
Filed:
September 19, 2011
Date of Patent:
November 25, 2014
Assignees:
Kabushiki Kaisha Toshiba, National University Corporation Tohoku University
Abstract: A ferromagnetic graphene includes at least one antidot such that the ferromagnetic graphene has ferromagnetic characteristics. A spin valve device includes a ferromagnetic graphene. The ferromagnetic graphene includes a first region, a second region, and a third region. At least one antidot is formed in each of the first region and the third region. The first region and the third region are ferromagnetic regions, whereas the second region is a non-ferromagnetic region.
Abstract: FePt-based heat assisted magnetic recording (HAMR) media comprising a thick granular FePt:C magnetic recording layer capable of maintaining a single layer film having desirable magnetic properties. According to one embodiment, the thick granular FePt:C magnetic recording layer comprises a plurality of carbon doped FePt alloy columnar grains, where the plurality of carbon doped FePt alloy columnar grains comprise a carbon gradient along the thickness of the hard magnetic recording layer.
Type:
Grant
Filed:
August 20, 2010
Date of Patent:
November 18, 2014
Assignee:
WD Media, LLC
Inventors:
Hua Yuan, Alexander Chernyshov, B. Ramamurthy Acharya
Abstract: Provided is a magnetic recording medium achieving both of reduction in switching field distribution and reduction in switching field intensity by high-frequency magnetic field, thus enabling high-density recording. Magnetic grains of the magnetic recording medium are made up of a recording layer and a resonance layer. The resonance layer is disposed closer to a protective layer 5 than the recording layer, and a magnetic material of the recording layer has anisotropy field 1.2 times or more anisotropy field of a magnetic material of the resonance layer. The magnetic material of the recording layer has saturation magnetization substantially equal to saturation magnetization of the magnetic material of the resonance layer. At the entire resonance layer and a part of the recording layer, the magnetic grains are separated from surrounding magnetic grains by a nonmagnetic material, and at a part of the recording layer, the magnetic grains are coupled with surrounding magnetic grains.
Abstract: Provided are a magnetic disk comprising a granular magnetic recording layer which causes less noise even with a recording capacity thereof of 250 G or more bits per square inch; and a method for manufacturing the same. The magnetic disk according to the present invention comprises: a granular magnetic recording layer (20) which is formed on a disk substrate 10 directly or via an intermediate layer and which has non-magnetic regions between granular columnar particles; and an auxiliary recording layer (22) which is formed on the granular magnetic recording layer 20 and which causes exchange interaction among the granular columnar particles, wherein the auxiliary recording layer (22) contains 0.1 to 3 moles of oxygen.
Abstract: A method for providing a capping layer configured for an energy assisted magnetic recording (EAMR) head including at least one slider. The method comprises etching a substrate having a top surface using an etch to form a trench in the substrate, the trench having a first surface at a first angle from the top surface and a second surface having a second angle from the top surface. The method further comprises providing a protective coating exposing the second surface and covering the first surface, removing a portion of the substrate including the second surface to form a laser cavity within the substrate configured to fit a laser therein, and providing a reflective layer on the first surface to form a mirror, the cavity and mirror being configured for alignment of the laser to the laser cavity and to the mirror and for bonding the laser to the laser cavity.
Abstract: According to one embodiment, a perpendicular magnetic recording medium includes a substrate, and a multilayered magnetic recording layer formed on the substrate by alternately stacking two or more magnetic layers and two or more nonmagnetic layers. The magnetic layers and nonmagnetic layers of the multilayered magnetic recording layer are continuous layers. The magnetic layer includes a magnetic material portion, and a plurality of pinning sites dispersed in the magnetic material portion and made of a nonmagnetic metal different from a nonmagnetic material as a main component of the nonmagnetic layer. This perpendicular magnetic recording medium has magnetic characteristics by which a gradient ? of a magnetization curve near the coercive force is 5 or more.
Abstract: A perpendicular magnetic recording medium with SNR improved by reducing noise due to an auxiliary recording layer so that a higher recording density can be achieved. The perpendicular magnetic recording medium 100 includes a base, at least a magnetic recording layer 122 having a granular structure in which a non-magnetic grain boundary portion is formed between crystal particles grown in a columnar shape; a non-magnetic split layer 124 disposed on the magnetic recording layer 122 and containing Ru and oxygen; and an auxiliary recording layer 126 that is disposed on the split layer 124 and that is magnetically approximately continuous in an in-plane direction of a main surface of the base 110.