With Pretreatment Of Base Patents (Class 427/129)
  • Publication number: 20100068512
    Abstract: Disclosed is a magnetic material for a high frequency wave which has high magnetic permeability and small eddy-current loss, particularly a magnetic material for a high frequency wave which can be used suitably in an information device which works in a high frequency field of 1 GHz or higher. Specifically disclosed is a composite magnetic material for a high frequency wave, which comprises a (rare earth element)-(iron)-(nitrogen)-based magnetic material and a (rare earth element)-(iron)-(nitrogen)-based magnetic material whose surface is coated with a ferrite magnetic material.
    Type: Application
    Filed: April 25, 2008
    Publication date: March 18, 2010
    Inventors: Nobuyoshi Imaoka, Masanori Abe, Takashi Nakagawa, Sasaru Tada
  • Publication number: 20100033872
    Abstract: A bit patterned media (BPM) includes many magnetic dots arranged in tracks on a substrate. The magnetic dots each have a hard magnetic core, a soft magnetic cladding surrounding the core and a thin non-magnetic layer that separates the hard magnetic core from the soft magnetic ring. The soft magnetic cladding stabilizes the magnetization at the edges of the hard magnetic core to improve the signal to noise ratio of the magnetic dots. The soft magnetic rings also narrow the magnetic field of the dots which reduces the space requirements and allows more dots to be placed on the substrate.
    Type: Application
    Filed: July 1, 2009
    Publication date: February 11, 2010
    Inventors: Haiwen Xi, Kaizhong Gao, Song S. Xue
  • Publication number: 20100021767
    Abstract: A method of fabricating a discrete track magnetic recording media. A base layer is provided onto which repeating and alternating magnetic layer and non-magnetic layers are deposited. The thickness of the magnetic layer corresponds to the width of the track of the recording media. A cylindrical rod can be used as the base layer, such that the alternating magnetic and non-magnetic layers spiraling or concentric layers around the rod. The resulting media layer can be cut or sliced into individual magnetic media or used to imprint other media discs with the discrete pattern of the media layer.
    Type: Application
    Filed: July 23, 2008
    Publication date: January 28, 2010
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Nurul Amin, Sining Mao
  • Publication number: 20090280241
    Abstract: This invention provides a method for manufacturing a glass substrate for a magnetic disk comprising a chemical strengthening step. The method provides a glass substrate for a magnetic disk that can suppress the occurrence of very small waves in cooling a glass substrate after the chemical strengthening step, and, while preventing troubles such as head crush and thermal asperity, can realize lowered flying height of a magnetic head and high-density information recording, and is particularly suitable for application to small-size magnetic disks for portable information equipment. In the step of cooling after the chemical strengthening step, cooling treatment is carried out in which the glass substrate is brought into contact with a treatment liquid containing a melt of a material having a solidification temperature below that of a chemical strengthening salt.
    Type: Application
    Filed: March 15, 2007
    Publication date: November 12, 2009
    Applicant: HOYA CORPORATION
    Inventor: Katsuyuki Iwata
  • Publication number: 20090274932
    Abstract: A sputtered metal film recording medium includes a substrate, a texture promotion layer sputtered on a first side of the substrate, a seed layer deposited on the texture promotion layer, an intermediate layer including a chromium alloy deposited on the seed layer, and a longitudinal magnetic recording layer including a cobalt alloy deposited on the intermediate layer. The texture promotion layer configures in-plane orientation of a cobalt structure in the magnetic recording layer.
    Type: Application
    Filed: May 2, 2008
    Publication date: November 5, 2009
    Inventors: Mallika Kamarajugadda, Jixiong Han, Joseph Skorjanec
  • Patent number: 7596854
    Abstract: A method is disclosed for fabricating a read head for a magnetic disk drive having a read head sensor and a hard bias layer, where the read head has a shaped junction between the read head sensor and the hard bias layer. The method includes providing a layered wafer stack to be shaped. A single- or multi-layered photoresist mask having no undercut is deposited upon the layered wafer stack to be shaped. The layered wafer stack is shaped by the output of a milling source, where the shaping includes partial milling to within a partial milling range to form a shaped junction. A hard bias layer is then deposited which is in contact with the shaped junction of the wafer stack.
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: October 6, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Marie-Claire Cyrille, Wipul Pemsiri Jayasckara, Mustafa Michael Pinarbasi
  • Publication number: 20090154017
    Abstract: A bit patterned magnetic media design for reducing the amount of magnetic material located in the trenches between topographic features is disclosed. An intermediate non-magnetic layer is deposited on the topography prior to depositing the functional magnetic layer on the topographic substrate features. The non-magnetic layer increases the width of the land regions that will ultimately support the functional magnetic layer. The non-magnetic layer also reduces the amount of trench deposition that can occur in the subsequent deposition of the magnetic recording layer. By eliminating most of the magnetic trench material, the amount of magnetic flux and readback interference produced by the trench material is reduced to an acceptable level.
    Type: Application
    Filed: December 17, 2007
    Publication date: June 18, 2009
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS BV
    Inventors: Thomas Robert Albrecht, Olav Hellwig
  • Publication number: 20090142625
    Abstract: The present invention provides a magnetic recording medium which enables improvement of the layer quality of magnetic layer grown on the surface of a soft magnetic underlayer by conducting excellent control of crystal orientation by imparting an optimal half-width of the Rocking curve (??50), as well as obtainment of SNR that suppresses generation of TA and enables realization of high-density recording. The magnetic recording medium includes a soft magnetic underlayer, an orientation control layer, a perpendicular magnetic recording layer, and a protective layer, which are disposed on top of a non-magnetic substrate; wherein the magnetic anisotropy ratio (Hmr/Hmc) of the soft magnetic underlayer is 1 or less, and ??50 is 1 to 6 degrees.
    Type: Application
    Filed: July 12, 2006
    Publication date: June 4, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Masato Fukushima, Yuji Murakami, Kenji Shimizu
  • Publication number: 20090136659
    Abstract: In a method in which a cut line is formed on one surface of a planar glass material, and the cut line is allowed to extend in the thickness direction of the glass material, thereby cutting a glass substrate from the glass material, the cut line is selectively formed on a surface having relatively small surface waviness out of two opposing surfaces of the glass material. In the case of a glass material formed into a planar shape on a molten metal, the surface which has come into contact with the molten metal is selected as the surface having relatively small surface waviness. When a disk-shaped glass substrate is cut from the glass material, cutting is performed under conditions where either one of the thickness and the radius of the glass material and the maximum height of surface waviness of the glass material satisfy a predetermined relationship.
    Type: Application
    Filed: March 23, 2007
    Publication date: May 28, 2009
    Applicants: HOYA CORPORATION, HOYA GLASS DISK PHILIPPINES, INC.
    Inventors: Joseph Marquez, Elmer Mahia
  • Publication number: 20090130492
    Abstract: Information storage devices and methods of manufacturing the same are provided. An information storage device includes a magnetic layer formed on an underlayer. The underlayer has at least one first region and at least one second region. The first and second regions have different crystallinity characteristics. The magnetic layer has at least one third region formed on the at least one first region and at least one fourth region formed on the at least one second region. The third and fourth regions have different magnetic anisotropic energy constants.
    Type: Application
    Filed: May 6, 2008
    Publication date: May 21, 2009
    Inventors: Sung-chul Lee, Sun-ae Seo, Young-jin Cho, Chang-won Lee
  • Publication number: 20090097159
    Abstract: A manufacturing method for a perpendicular magnetic recording head includes the steps of forming a groove in a first nonmagnetic layer, forming a side shield, forming a second nonmagnetic layer, forming a main-magnetic-pole front end portion and forming a main-magnetic-pole yoke portion. The groove extends in a front-rear direction orthogonal to an air bearing surface. The side shield of soft magnetic material, the second nonmagnetic layer and the main-magnetic-pole front end portion of soft magnetic material are formed on an inner wall of the groove. The main-magnetic-pole front end portion is not magnetostatically coupled to the side shield. The main-magnetic-pole yoke portion magnetically is insulated from the side shield and magnetically connected to the main-magnetic-pole front end portion. The main-magnetic-pole yoke portion widens from the main-magnetic-pole front end portion toward a rear side.
    Type: Application
    Filed: September 23, 2008
    Publication date: April 16, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Mitsuru Otagiri, Hiroshi Shirataki, Yuko Miyake
  • Patent number: 7514118
    Abstract: A method of plating on a glass substrate allowing an electroless plating film with good adhesiveness to be formed by chemically bonding a silane coupling agent in a state of simple adhesion or hydrogen bond to the surface of the glass substrate through dehydration condensation reaction, and a method of manufacturing a magnetic recording medium using the plating method. In the plating method, electroless plating is performed on a glass substrate after sequentially conducting at least the adhesion layer formation that forms an adhesion layer using a silane coupling agent solution, catalyst layer formation, a catalyst activation, and a drying that chemically bonds the silane coupling agent in the adhesion layer to the surface of the glass substrate.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: April 7, 2009
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventors: Akira Iso, Youichi Tei
  • Patent number: 7500303
    Abstract: A read head for a disk drive and a method of fabricating the read head with overlaid lead pads that contact the top surface of the sensor between the hardbias structures to define the electrically active region of the sensor are described. The invention deposits the GMR and lead layers before milling away the unwanted material. A photoresist mask with a hole defining the active area of the sensor is preferably patterned over a layer of DLC that is formed into a mask. A selected portion of the exposed lead material is then removed using the DLC as a mask defining the active region of the sensor. A photoresist mask pad is patterned to define the full sensor width. The excess sensor and lead material exposed around the mask is milled away. The layers for the hardbias structure are deposited.
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: March 10, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Tsung Yuan Chen, Kuok San Ho, Mustafa Michael Pinarbasi
  • Publication number: 20090029041
    Abstract: The invention provides a method of cleaning a magnetic recording medium substrate that removes residual substances and suppresses oxidation of the substrate surface. The method of cleaning the magnetic recording medium substrate uses nano-bubble water. Also disclosed is a method of manufacturing a magnetic recording medium that includes the method of cleaning the magnetic recording medium substrate and steps of sequentially forming at least a magnetic layer, a protective layer, and a liquid lubricant layer on the cleaned substrate.
    Type: Application
    Filed: July 10, 2008
    Publication date: January 29, 2009
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventors: Jun Natsume, Shoji Sakaguchi, Takashi Shimada
  • Publication number: 20090011280
    Abstract: The present invention relates to a magnetic head manufacturing method used for a magnetic storage device. The method includes the steps of forming a first groove in a shape corresponding to an outline of a main magnetic pole on an insulation layer; forming a second groove corresponding to an outline of a main magnetic pole brace layers; inside the outline of the main magnetic pole; and using a plating method to fill the first and second grooves at the same time with a ferromagnetic material and form a main magnetic pole and a main magnetic pole brace layer at the same time.
    Type: Application
    Filed: October 19, 2007
    Publication date: January 8, 2009
    Applicant: Fujitsu Limited
    Inventor: Kazuaki Inukai
  • Publication number: 20090004510
    Abstract: A substrate for perpendicular magnetic recording medium 2 is provided with a soft magnetic substrate coat 5. On this soft magnetic substrate coat 5, an anticorrosion coat 5 is formed. The anticorrosion coat 6 is preferably formed so as to completely cover the entire soft magnetic substrate coat 5.
    Type: Application
    Filed: August 25, 2005
    Publication date: January 1, 2009
    Applicant: SHOWA DENKO K.K.
    Inventor: Masahiro Ohmori
  • Publication number: 20080291578
    Abstract: This perpendicular magnetic recording medium has a nonmagnetic substrate and a magnetic recording structure formed above the substrate. The magnetic recording structure has at least a soft magnetic underlayer, an intermediate layer and a magnetic layer. The substrate has a surface profile curve whose angle of inclination is 2.0 degree or less, or whose surface roughness of the substrate, with cycle (wavelength components) in the ranges of 83 nm or less to 30 nm or less, is 0.15 nm or less.
    Type: Application
    Filed: May 19, 2008
    Publication date: November 27, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Masaru Ono, Yuki Yoshida, Kiyoshi Yamaguchi, Akira Kikuchi
  • Patent number: 7435488
    Abstract: Described is a structural body including at least partially an aluminum member having on a surface an anodized film with micropores present, in which: the micropores have a coefficient of variation in pore size of 5 to 50%; and the micropores are each sealed with a metal. The structural body can generate localized plasmon resonance having a sufficiently large intensity and be produced at low cost through a simple production process, and having a large surface area.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: October 14, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Tadabumi Tomita, Yoshinori Hotta, Akio Uesugi
  • Publication number: 20080244896
    Abstract: A method for manufacturing a magnetic write head for perpendicular magnetic recording. The method includes the formation of a write pole over a substrate. A non-magnetic side gap layer is deposited and an ion milling is used to remove a portion of the substrate to lower the floor of the substrate. A sacrificial fill layer can then be deposited. A chemical mechanical polishing process can be used to remove the mask structure remaining as a remnant of the formation of the write pole, and then the sacrificial fill layer can be removed. A non-magnetic, electrically conductive material can be deposited to form a trailing gap, and a magnetic material can then be deposited to form a wrap around trailing shield.
    Type: Application
    Filed: March 20, 2007
    Publication date: October 9, 2008
    Inventors: Christian Rene Bonhote, Quang Le, Neil Leslie Robertson, Petrus Antonius Van Der Heijden
  • Publication number: 20080241369
    Abstract: A magnetic data track used in a magnetic shift register memory system may be fabricated by forming a multilayered stack of alternating dielectric and/or silicon layers. A trench is etched in the multi-layer stack structure. A selective etching process is used to corrugate the walls of trench. A seed layer is applied to the walls and bottom of the trench; the seed layer is covered with a magnetic layer. The trench is filled with an insulating material. A patterned layer is applied and portions of insulating material exposed by the pattern are removed, forming holes. Magnetic material and seed layer exposed in holes is selectively removed. The holes are filled with insulating material and connecting leads are attached to data tracks.
    Type: Application
    Filed: May 2, 2008
    Publication date: October 2, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Tze-chiang Chen, Stuart S.P. Parkin
  • Publication number: 20080241603
    Abstract: A magnetic disk glass substrate including compressive stress layers at main surfaces and a tensile stress layer between the compressive stress layers formed by chemical strengthening. When the glass substrate has a thickness of less than 0.5 mm and the tensile stress layer has a thickness L and a tensile stress of Pt (kg/mm2), the following relation holds: 0.4 (kg/mm)?L·Pt?2.
    Type: Application
    Filed: March 24, 2005
    Publication date: October 2, 2008
    Inventor: Hideki Isono
  • Publication number: 20080218841
    Abstract: Magneto-optical crystals of each pixel of a magneto-optical device are magnetically and completely separated, and the entire surface thereof is flattened. Disclosed is a magneto-optical device including a non-magnetic substrate, a magneto-optical crystal embedded in recessed portions formed in the surface of the non-magnetic substrate at positions where pixels are to be located, and a partitioning wall monolithic with the non-magnetic substrate and magnetically separating the magneto-optical crystal from each other at the position of a gap between the pixels, wherein the entire surface of the magneto-optical device is flattened.
    Type: Application
    Filed: February 24, 2006
    Publication date: September 11, 2008
    Applicant: FDK CORPORATION
    Inventors: Katsuhiro Iwasaki, Hiromitsu Umezawa
  • Publication number: 20080213469
    Abstract: A method and apparatus for high density nanostructures is provided. The method and apparatus include Nano-compact optical disks, such as nano-compact disks (Nano-CDS). In one embodiment a 400 Gbit/in2 topographical bit density nano-CD with nearly three orders of magnitude higher than commercial CDS has been fabricated using nanoimprint lithography. The reading and wearing of such Nano-CDS have been studied using scanning proximal probe methods. Using a tapping mode, a Nano-CD was read 1000 times without any detectable degradation of the disk or the silicon probe tip. In accelerated wear tests with a contact mode, the damage threshold was found to be 19/N. This indicates that in a tapping mode, both the Nano-CD and silicon probe tip should have a lifetime that is at least four orders of magnitude longer than that at the damage threshold.
    Type: Application
    Filed: October 31, 2007
    Publication date: September 4, 2008
    Inventor: Stephen Y. Chou
  • Patent number: 7409759
    Abstract: Provided is a method and system for manufacturing a hard drive platen. The method includes depositing two or more types of film around a central core to form a plurality of film layers, each film layer being of a different type than its adjacent layers. Next, the deposited film layers are sectioned to expose a patterned surface. The patterned surface is then planarized and selectively etched to expose patterns comprised of one of the types of film to a predetermined depth to produce a selectively etched surface. Magnetic material it deposited within etches of the surface and the surface is then planarized to form separated magnetic tracks therein.
    Type: Grant
    Filed: December 16, 2004
    Date of Patent: August 12, 2008
    Assignee: ASML Holding N.V.
    Inventor: Harry Sewell
  • Publication number: 20080187654
    Abstract: The process of forming a plated film according to the invention is designed such that the surface asperities of the inorganic film formed by the tracing of a standing wave occurring at the inner wall surface of the first opening in the resist at the resist pattern-formation step are reduced or eliminated. It is thus possible to form, efficiently yet in a short period of time, a high aspect-ratio plated film portion having an aspect ratio of greater than 1. In addition, the formed plated film quality is extremely improved for the absence of pores (cavities).
    Type: Application
    Filed: February 6, 2007
    Publication date: August 7, 2008
    Applicant: TDK CORPORATION
    Inventors: Akifumi Kamijima, Hitoshi Hatate, Hideyuki Yatsu
  • Publication number: 20080151441
    Abstract: A magnetoresistive sensor having magnetically anisotropic bias layers for biasing the free layer of the sensor. The sensor includes a sensor stack with a pinned layer structure and a free layer structure and having first and second sides. Hard bias structures for biasing the magnetization of the free layer are formed at either side of the sensor stack, and each of the hard bias structure includes a hard magnetic layer that has a magnetic anisotropy to enhance the stability of the biasing. The hard bias structure can include a Cr under-layer having a surface that has been treated by a low power angled ion milling to form it with an anisotropic surface texture. A layer of Cr—Mo alloy is formed over the Cr under-layer and the hard magnetic material layer is formed over the Cr—Mo alloy layer. The anisotropic surface texture of the Cr layer induces an aligned crystalline structure in the hard magnetic layer that causes the hard magnetic layer to have a magnetic anisotropy.
    Type: Application
    Filed: December 22, 2006
    Publication date: June 26, 2008
    Inventors: James Mac Freitag, Mustafa Michael Pinarbasi, Wipul Pemsiri Jayasekara
  • Publication number: 20080145522
    Abstract: A nanohole structure includes a metallic matrix and nanoholes arrayed regularly in the metallic matrix, in which the nanoholes are spaced in rows at specific intervals to constitute rows of nanoholes. The rows of nanoholes are preferably arranged concentrically or helically. The nanoholes in adjacent rows of nanoholes are preferably arranged in a radial direction. The width of each row of nanoholes preferably varies at specific intervals in its longitudinal direction. A magnetic recording medium includes a substrate, and a porous layer on or above the substrate. The porous layer contains nanoholes each extending in a direction substantially perpendicular to a substrate plane, containing at least one magnetic material therein, and is the above-mentioned nanohole structure.
    Type: Application
    Filed: November 21, 2007
    Publication date: June 19, 2008
    Applicants: FUJISTU LIMITED, KANAGAWA ACADEMY OF SCIENCE AND TECHNOLOGY
    Inventors: Ken-ichi Itoh, Hiroshi Nakao, Hideyuki Kikuchi, Mineo Moribe, Hideki Masuda
  • Patent number: 7386930
    Abstract: For forming an annular magnetostrictive coat on an outer peripheral surface of a rotational shaft associated with a magnetostrictive torque sensor, a magnetostrictive coat forming method comprises a step of fitting a cylindrical masking jig over the outer peripheral surface of the rotational shaft and securing the masking jig to the outer peripheral surface, a step of placing the rotational shaft in a plating tank to thereby form the magnetostrictive coat by plating on the outer peripheral surface, and a step of detaching the masking jig from the rotational shaft.
    Type: Grant
    Filed: November 7, 2007
    Date of Patent: June 17, 2008
    Assignee: Honda Motor Co., Ltd.
    Inventors: Yasuo Shimizu, Yoshito Nakamura, Shunichiro Sueyoshi, Nobuhiko Yoshimoto, Koji Kobayashi, Yuichi Fukuda, Mizuho Doi, Hitoshi Harada, Tomohiro Hoshi
  • Patent number: 7370410
    Abstract: Wirings 2B1 are formed by application of heat treatment after an ink jet system is used to discharge a conductive liquid L onto a provisional substrate 5 having a predetermined repellent property, bonding an insulating layer 4B1 to the wirings 2B1 with an adhesive material 3B1 therebetween, peeling and removing the provisional substrate 5, and bonding and fixing the wirings 2B1 together with the insulating film 4B1 to a main substrate 1 by an adhesive material 3B1.
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: May 13, 2008
    Assignee: Seiko Epson Corporation
    Inventor: Takashi Hashimoto
  • Patent number: 7361419
    Abstract: A substrate for a perpendicular magnetic recording medium has a soft magnetic underlayer that functions as a soft magnetic backing layer of a perpendicular magnetic recording medium. The substrate for a perpendicular magnetic recording medium has a nonmagnetic base made of Al—Mg alloy or the like. The soft magnetic underlayer is formed of a Ni—P alloy containing phosphorus in a range of 0.5 wt % to 6 wt % formed by electroless plating on the nonmagnetic base. The substrate can also include a nonmagnetic underlayer formed by electroless plating on the base before electroless plating the soft magnetic underlayer. To form the perpendicular magnetic recording medium, the surface of the soft magnetic is textured using free abrasive grains. Thereafter, a nonmagnetic seed layer, a magnetic recording layer, and a protective layer can be formed by sputtering. A soft magnetic supplemental layer also can be formed on the soft magnetic underlayer before forming the seed layer.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: April 22, 2008
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventors: Hiroyuki Uwazumi, Yasushi Sakai, Mitsuo Masuda, Norihiko Nakajima
  • Publication number: 20080014470
    Abstract: A method for manufacturing a glass substrate which has a uniform and minute pattern of stripes formed on the surface thereof by ultraprecision polishing, and which allows the recording capacity of a magnetic disk to be increased, includes an inspecting step before the glass substrate is subjected to ultraprecision polishing, whether the Young's modulus Es in topmost part as determined by the nanoindentation method and the Young's modulus Eg as determined by ultrasonic resonance fulfill the inequality 0.8 Eg<Es<1.2 Eg; or the hardness Hs in topmost part as determined by the nanoindentation method and the Vickers hardness Hv fulfill the inequality 0.8 Hv<Hs<1.2 Hv.
    Type: Application
    Filed: July 9, 2007
    Publication date: January 17, 2008
    Inventor: Hideki Kawai
  • Patent number: 7310870
    Abstract: For forming an annular magnetostrictive coat on an outer peripheral surface of a rotational shaft associated with a magnetostrictive torque sensor, a magnetostrictive-coat forming method comprises a step of fitting a cylindrical masking jig over the outer peripheral surface of the rotational shaft and securing the masking jig to the outer peripheral surface, a step of placing the rotational shaft in a plating tank to thereby form the magnetostrictive coat by plating on the outer peripheral surface, and a step of detaching the masking jig from the rotational shaft.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: December 25, 2007
    Assignee: Honda Motor Co., Ltd.
    Inventors: Yasuo Shimizu, Yoshito Nakamura, Shunichiro Sueyoshi, Nobuhiko Yoshimoto, Koji Kobayashi, Yuichi Fukuda, Mizuho Doi, Hitoshi Harada, Tomohiro Hoshi
  • Patent number: 7297363
    Abstract: In the method for producing a magnetic recording medium having a nonmagnetic substrate coated with a magnetic coating material containing a ferromagnetic powder and a binder, the magnetic coating material contains a liquid A constituted by the ferromagnetic powder and a solvent, and a solution B of the binder, and the liquid A and the solution B are mixed together by applying an ultrasonic wave thereto, and are thereafter subjected to dispersion processing. Thereby, coagulated particles of the ferromagnetic powder can be dispersed and the coagulation of the ferromagnetic powder can be prevented, thus making it possible to obtain a liquid of ferromagnetic powder with uniform adsorption of the binder. As a result, a magnetic coating material suitable for a low-noise high-density coating-type magnetic recording medium is obtained.
    Type: Grant
    Filed: June 24, 2003
    Date of Patent: November 20, 2007
    Assignee: FUJIFILM Corporation
    Inventor: Koji Naoe
  • Publication number: 20070218318
    Abstract: A magnetic recording medium having magnetic dots that can achieve high density recording is disclosed. The magnetic recording medium comprises at least an underlayer, a magnetic recording layer, and a protective layer sequentially laminated on a nonmagnetic substrate. The underlayer is composed of ruthenium or an alloy of mainly ruthenium and has an undulating structure formed with ridge lines in a predetermined pitch on the surface of the underlayer. The magnetic recording layer contains at least ferromagnetic crystal grains and a nonmagnetic component. Magnetic dots composed of crystal grains with a grain size not smaller than 4 nm in the magnetic recording layer are aligned on a surface of the underlayer along the ridge line, and each of the magnetic dots s separated by the nonmagnetic component from each other. A simple manufacturing method for this medium also is disclosed.
    Type: Application
    Filed: March 7, 2007
    Publication date: September 20, 2007
    Applicant: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventor: Sadayuki WATANABE
  • Patent number: 7267841
    Abstract: An information-storage media is provided that includes: (a) a substrate disk 312 having first and second opposing surfaces; (b) a first interface layer 304 on the first surface, the first interface layer having a first thickness; (c) a second interface layer 308 on the second surface, the second interface layer having a second thickness, wherein the first and second interface layers have a different chemical composition than the substrate disk; and (d) an information-storage layer 412 adjacent to one or both of the interface layers. The first and second thicknesses are different to provide an unequal stress distribution across the cross-section of the media.
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: September 11, 2007
    Assignee: Maxtor Corporation
    Inventors: Kwang Kon Kim, Ramon Clasara
  • Patent number: 7241501
    Abstract: An iron nitride magnetic powder comprised primarily of Fe16N2 phase is characterized in that its coercive force Hc is 200 KA/m or greater and bulk switching field distribution BSDF is 2 or less. The magnetic powder can be produced by allowing a nitriding reaction of Fe particles with a nitrogen-containing gas for producing nitrided particles of primarily Fe16N2 phase to proceed under an increased pressure of 0.1 MPa or greater. The enhanced properties of the iron nitride magnetic powder make it suitable as a magnetic material for high-density magnetic recording media.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: July 10, 2007
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Kenji Masada, Takafumi Amino, Akira Nagatomi
  • Patent number: 7238384
    Abstract: Proposed are a substrate that comprises an easily producible soft magnetic backing film and can reduce spike noise from the soft magnetic backing film, and a method for producing the substrate. More specifically, provided are a substrate for a perpendicular magnetic recording hard disk medium, comprising an Si single crystal substrate (1) having a diameter of 65 mm or less, a thickness of 1 mm or less and an average surface roughness (Rms) of 1 nm or more and 1000 nm or less; an under-plated layer (2) formed on the substrate, the layer (2) comprising one or more metals selected from a group consisting of Ni, Cu and Ag and having a thickness of 1 nm to 300 nm; and a plated soft magnetic layer (3) formed on the under-plated layer, the layer (3) having a thickness of 50 nm or more and less than 1000 nm, a coercivity of 20 Oe(oersteds) or less and a saturation magnetization of 1T or more, wherein the average surface roughness (Rms) of the plated soft magnetic layer is 0.1 nm or more and 5 nm or less.
    Type: Grant
    Filed: July 14, 2005
    Date of Patent: July 3, 2007
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventor: Toshihiro Tsumori
  • Patent number: 7228619
    Abstract: A method for fabricating a coil and pedestal for a write head using a common seed layer is described. A nonmetallic gap layer is deposited on a planarized pole piece surface. Openings for the pole piece pedestal and the back gap pole piece are etched through the nonmetallic gap layer. A seed layer comprising a magnetic material is deposited on the etched gap layer. Preferably the coil is fabricated first on the planar surface of the seed layer. The coil structure, the pedestal pole piece, back-gap pole piece, side and center tap connections are fabricated on the same seed layer. The remaining seed layer is removed, the coil is encapsulated, the wafer is refilled with alumina and the wafer is planarized. The prior art process can be resumed at this point. Optionally a second seed layer such as copper (Cu) can be used.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: June 12, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Quang Le
  • Patent number: 7219422
    Abstract: The fabrication of a semiconductor integrated circuit device involves testing using a pushing mechanism that is constructed by forming, over the upper surface of a thin film probe, a reinforcing material having a linear expansion coefficient (thermal expansion coefficient) almost equal to that of a wafer to be tested; forming a groove in the reinforcing material above a contact terminal; placing an elastomer in the groove so that a predetermined amount projects out of the groove; and disposing a pusher and another elastomer to sandwich the pusher between the elastomers. With the use of such a probe, it is possible to improve the throughput of wafer-level electrical testing of a semiconductor integrated circuit.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: May 22, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Yuji Wada, Susumu Kasukabe, Takehiko Hasebe, Yasunori Narizuka, Akira Yabushita, Terutaka Mori, Akio Hasebe, Yasuhiro Motoyama, Teruo Shoji, Masakazu Sueyoshi
  • Patent number: 7220447
    Abstract: A process for producing a magnetic recording medium, which process comprises a texturing step for forming texture grooves having a line density of 7,500 lines/mm or more on the surface of a non-metallic substrate, and a step for forming an orientation-determining film, a non-magnetic undercoat layer, and a magnetic layer on the non-metallic substrate.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: May 22, 2007
    Assignee: Showa Denko K.K.
    Inventors: Masato Fukushima, Ryuji Sakaguchi, Yukihisa Matsumura
  • Patent number: 7220446
    Abstract: There are disclosed an information recording medium substrate having a surface roughness of Rmax 15 nm or less, and an information recording medium, particularly an information recording medium substrate and information recording medium in which for surfaces of the substrate and medium, a bearing area value (offset bearing area value) in a depth of 0.5 to 5 nm (predetermined slice level) from a bearing height (real peak height) corresponding to the bearing area value of 0.2% to 1.0% is 90% or less, and a manufacture method of the substrate and medium.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: May 22, 2007
    Assignee: Hoya Corporation
    Inventors: Tomotaka Yokoyama, Hiroshi Tomiyasu, Masatomo Shibui, Nobuyuki Eto
  • Patent number: 7189438
    Abstract: A magnetic recording medium has a recording layer, disposed above a surface of a substrate and made of hard magnetic nano-particles. The hard magnetic nano-particles are made of an alloy having as a main component an element selected from a group consisting of FePt, FePd and CoPt, and the hard magnetic nano-particles have axes of easy magnetization oriented in a direction approximately perpendicular to the surface of the substrate.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: March 13, 2007
    Assignee: Fujitsu Limited
    Inventors: Satoru Momose, Hiroyoshi Kodama, Nobutaka Ihara
  • Patent number: 7183012
    Abstract: The invention provides a magnetic recording medium and a method of manufacturing the magnetic recording medium, in which a high density and good storage stability can be achieved by giving anisotropy in shape to a magnetic substance. A plan shape of the magnetic substance in the magnetic recording medium, which appears on the recording surface side, is an ellipse that is present within a rectangle and has a minor axis with a length equal to a short side of the rectangle. A quadrilateral defined by four intersects of two adjacent vertical rows and two adjacent horizontal rows, each of these rows comprising a plurality of pores, has a rectangular or rhombic shape.
    Type: Grant
    Filed: March 18, 2003
    Date of Patent: February 27, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsuya Saito, Tohru Den
  • Patent number: 7172786
    Abstract: The present invention discloses a method for the production of sub-micron structures on magnetic materials using electron beam lithography. A subtractive process is disclosed wherein a portion of a magnetic material layer is removed from the substrate using conventional lithography, and the remaining portion of the magnetic material layer is patterned by e-beam lithography. A additive process is also disclosed wherein a thin magnetic seed layer is deposited on the substrate, a portion of which is removed by conventional lithography and replaced with a non-magnetic conducting layer. The remaining portion of magnetic seed layer is patterned by e-beam lithography and the final magnetic structure produced by electroplating.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: February 6, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Alexander Adrian Girling Driskill-Smith, Hieu Lam, Kim Y. Lee
  • Patent number: 7166318
    Abstract: A production method and a production apparatus for a magnetic recording medium, which enable the efficient production of a discrete type magnetic recording medium, while reliably preventing any deterioration of the partitioned recording elements.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: January 23, 2007
    Assignee: TDK Corporation
    Inventors: Kazuhiro Hattori, Mitsuru Takai, Takahiro Suwa
  • Patent number: 7160572
    Abstract: In a spin tunnel magnetoresistive effect film in which a magnetic thin film to which an exchange bias is applied by exchange coupling via an anti-ferromagnetic thin film and a magnetic thin film that detects a magnetic field are laminated, a magnetic thin film or an anti-ferromagnetic thin film (PtMn, PdMn, NiMn) is laminated onto an underlayer (Ta, Zr, Hf), the surface roughness thereof being in the range from 0.1 to 5 Angstroms. A means used to control the surface roughness introduces into the film growing chamber oxygen, nitrogen, hydrogen, or a gas mixture thereof into a vacuum of 10?6 Torr to 10?9 Torr, reduces the substrate temperature to 0° C. or lower during film growth, or oxidizes an underlayer. The lower electrode layer material used is a film laminate of a high-permeability amorphous magnetic material and a non-magnetic metallic layer.
    Type: Grant
    Filed: August 23, 2004
    Date of Patent: January 9, 2007
    Assignee: NEC Corporation
    Inventors: Junichi Fujikata, Tsutomu Ishi, Shigeru Mori
  • Patent number: 7150895
    Abstract: A perpendicular magnetic recording medium has a magnetic recording layer with ferromagnetic crystalline grains and nonmagnetic and nonmetallic grain boundary region surrounding the grains. The surface of its underlayer, before forming the magnetic recording layer, is exposed to an O2 or N2 atmosphere or an atmosphere of rare gas and O2 or N2, to attach the O2 or N2 as nucleation sites for promoting growth of the nonmagnetic and nonmetallic region. By forming the magnetic recording layer thereafter, both ferromagnetic crystalline grains and the nonmagnetic and nonmetallic grain boundary region are formed from the initial stage of the growth of the magnetic recording layer. Thus, a magnetic recording layer having excellent segregation structure can be formed.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: December 19, 2006
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Sadayuki Watanabe, Yasushi Sakai
  • Patent number: 7147944
    Abstract: The gas components in thermoplastic norbornene resin pellets are suppressed below certain levels by drying the resin under vacuum or under the ordinary pressure and under vacuum. A substrate for magnetic recording media is manufactured by injection-molding the resin dried by the method according to the invention. The magnetic recording medium, employing the substrate manufactured according to the invention, includes at least a magnetic layer, a protection layer on the magnetic layer and a liquid lubricant layer on the protection layer. The magnetic recording medium is manufactured by forming these layers, one after another, on the substrate according to the invention.
    Type: Grant
    Filed: February 20, 2004
    Date of Patent: December 12, 2006
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Youich Tei, Syoji Sakaguchi, Katsunori Suzuki
  • Patent number: 7141119
    Abstract: A pressure-controlling dispersion delivery system for delivering a sheared dispersion comprising a plurality of ingredients to a coating device selected from a direct feed delivery system and a coating device flow-through delivery system, wherein a coating formed from a dispersion delivered through the pressure-controlling delivery system has a more consistent caliper than a coating formed from a similar sheared dispersion delivered to a coating device by means of a gear pump delivery system.
    Type: Grant
    Filed: May 19, 2003
    Date of Patent: November 28, 2006
    Assignee: Imation Corp.
    Inventors: Travis A. Lemke, Mark Serafin
  • Patent number: 7131194
    Abstract: Wirings 2B1 are formed by application of heat treatment after an ink jet system is used to discharge a conductive liquid L onto a provisional substrate 5 having a predetermined repellent property, bonding an insulating layer 4B1 to the wirings 2B1 with an adhesive material 3B1 therebetween, peeling and removing the provisional substrate 5, and bonding and fixing the wirings 2B1 together with the insulating film 4B1 to a main substrate 1 by an adhesive material 3B1.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: November 7, 2006
    Assignee: Seiko Epson Corporation
    Inventor: Takashi Hashimoto