Plural Magnetic Deposition Layers Patents (Class 29/603.14)
  • Publication number: 20020181162
    Abstract: A disk drive write head (10) having a bottom pole (60), a first insulation layer (64) formed on the bottom pole (60), a coil (38) formed on the first insulation layer (64), a second insulation layer (66) formed on the coil (38), a write gap layer (76) formed on the second insulation layer (66), and a top pole (12) formed on the write gap layer (76), where the top pole (12) is substantially flat.
    Type: Application
    Filed: June 5, 2001
    Publication date: December 5, 2002
    Inventors: Yingjian Chen, James Wang, Qing He, Zi-Wen Dong, David J. Seagle
  • Publication number: 20020181163
    Abstract: A magnetoresistive (MR) read head is disclosed including a shield layer with a recessed portion and a protruding portion defined by the recessed portion. Also included is an MR sensor located in vertical alignment with the protruding portion of the shield layer. Further provided is at least one gap layer situated above and below the MR sensor. At least one of such gap layers is positioned in the recessed portion of the shield layer. By this design, a combined thickness of the gap layers is thinner adjacent to the MR sensor and the protruding portion of the shield layer, while being thicker adjacent to the recessed portion of the shield layer. As such, optimum insulation is provided while maintaining planar gap layer surfaces to avoid the detrimental ramifications of reflective notching and the swing curve effect.
    Type: Application
    Filed: June 5, 2001
    Publication date: December 5, 2002
    Inventor: Douglas Werner
  • Publication number: 20020181167
    Abstract: A magnetic field sensor is described incorporating a plurality of magnetic stripes spaced apart on the surface of a substrate such that the stray magnetic fields at the ends of the magnetic stripes are magnetostatically coupled and the magnetic stripes are magnetized respectively in alternating directions, nonmagnetic conductive material positioned in the spaces between the magnetic stripes and electrodes for passing current crosswise through the plurality of magnetic stripes to detect a change in resistance by the giant magnetoresistive effect (MGR). The invention overcomes the problem of detecting low magnetic fields since the magnetic fields required to saturate magnetic stripes depends on the magnetostatic coupling which in turn can be controlled by the geometry and position of the magnetic stripes in the sensor.
    Type: Application
    Filed: July 11, 2002
    Publication date: December 5, 2002
    Inventors: Richard Joseph Gambino, Thomas Penney, John Casimir Slonczewski
  • Publication number: 20020170165
    Abstract: A beveled writing pole includes a top portion, a beveled portion, and a throat portion. The top portion has an end that defines a writing pole tip. The beveled portion adjoins the top portion and has a bevel that extends from the writing pole tip and increases a thickness of the writing pole proximate the pole tip. The throat portion is formed of the top and beveled portions and has tapered sides that extend from the writing pole tip and increase a width of the writing pole proximate the writing pole tip. A method of forming the beveled writing pole is also presented.
    Type: Application
    Filed: January 4, 2002
    Publication date: November 21, 2002
    Inventors: Martin L. Plumer, Nurul Amin, Vee S. Kong, Richard P. Michel, Johannes Van ek
  • Patent number: 6483665
    Abstract: A bottom pole is divided into a bottom pole tip and a bottom pole layer. The bottom pole tip is formed on a flat surface of the bottom pole layer, and insulating layers made of inorganic materials are buried in a concave part between the bottom pole tip and a bottom connecting portion. The throat height is determined by the end close to the bottom pole tip of the insulating layer. An top pole tip is formed to be longer than the bottom pole tip on a write gap layer and is extended to a position facing part of a thin film coil. Mgnetomotive force from the thin film coil is conducted to the top pole tip efficiently, and a write characteristic of a thin film magnetic head is improved.
    Type: Grant
    Filed: December 6, 1999
    Date of Patent: November 19, 2002
    Assignee: TDK Corporation
    Inventor: Yoshitaka Sasaki
  • Publication number: 20020167767
    Abstract: A magnetic tunnel junction (MTJ) sensor in which the free layer longitudinal biasing elements are coupled, without insulation, to the free layer outside of the MTJ stack to provide reliable non-shunting MTJ free layer stabilization without extremely thin dielectric layers. In one embodiment, hard magnetic (HM) layers are disposed in contact with the free layer outside of and separated from the MTJ stack active region by a thick dielectric layer. In another embodiment, antiferromagnetic (AFM) bias layers are disposed in contact with the free layer outside of and separated from the MTJ stack active region by a thick dielectric layer. In other embodiments, nonconductive HM layers are disposed either in contact with the free layer outside of the MTJ stack active region and/or in abutting contact with the MTJ stack active region.
    Type: Application
    Filed: May 3, 2001
    Publication date: November 14, 2002
    Inventor: Wipul Jayasekara
  • Publication number: 20020167764
    Abstract: A suspended resist bridge suitable for lithographically patterning MR sensors having trackwidths narrower than 0.2 micron is fabricated using the method of the present invention. First, PMGI is spun onto a substrate to form a first thin resist layer. Next, PMMA is spun onto the first resist layer to form a second resist layer. The PMMA layer is exposed to an electron beam to pattern the trackwidth of the MR sensors. E-beam exposed PMMA is then developed in an IPA solution. The resist structure is then placed in a basic solution for dissolving PMGI, which results in a fully undercut resist bridge that is used for patterning the MR sensors.
    Type: Application
    Filed: May 10, 2001
    Publication date: November 14, 2002
    Inventors: Robert Edward Fontana, Jordan A. Katine, Jennifer Lu, Scott A. MacDonald, Michael J. Rooks, Hugo Alberto Emilio Santini
  • Patent number: 6477765
    Abstract: What is disclosed is a method of fabricating a thin film magnetic write transducer and the resulting write transducer structure. The method starts with the formation of a bottom pole of the write transducer on a base layer or substrate. This is followed by the formation of a write gap layer, formation of a coil, and formation a coil insulating layer. A thin top pole inner layer is then deposited over the entire structure. Next, a thick top pole outer layer is formed over the top pole inner layer. Preferably, the top pole outer layer is formed by plating through a photoresist mask that defines the top pole shape. Finally, the top pole inner layer is milled using the top pole outer layer as a mask. The top pole produced by this method has parallel sidewalls that are helpful in writing narrow data tracks. Use of the photoresist mask during plating of the top pole outer layer and ion milling of the top pole inner layer provides good dimensional control of the top pole's width.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: November 12, 2002
    Assignee: Storage Technology Corporation
    Inventor: Steven Charles Herrera
  • Patent number: 6473960
    Abstract: A method of manufacturing an active element for use with a magnetic head includes depositing a magnetic material to form a magnetic member, and nitriding the magnetic member after the depositing step. Preferably, the depositing step comprises depositing nickel-iron alloy, and the nitriding step comprises plasma nitriding the magnetic member. Advantageously, plasma nitriding may be performed at a temperature below 300 degrees Celsius to avoid adverse effects to components of the active element, such as organic planars. Active elements manufactured according to the method of the invention are also disclosed.
    Type: Grant
    Filed: January 7, 2000
    Date of Patent: November 5, 2002
    Assignee: Storage Technology Corporation
    Inventors: Bradford C. Schwartz, Steven C. Herrera
  • Publication number: 20020159200
    Abstract: A merged read/write magnetic recording head comprises a low magnetic moment first magnetic shield layer over a substrate. A read gap layer with a magnetoresistive head is formed over the first shield layer. A shared pole comprises a low magnetic moment second magnetic shield layer plated on a sputtered seed PLM layer over the read gap layer, a non-magnetic layer plated over the PLM layer and a HMM lower pole layer plated over the second magnetic shield layer. A write gap layer is formed over the first high magnetic moment pole layer of the shared pole. An upper pole comprises a high magnetic moment pole layer over the write gap layer.
    Type: Application
    Filed: April 24, 2002
    Publication date: October 31, 2002
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Kochan Ju, Cherng-Chyi Hau, Po-Kang Wang, Mao-Min Chen, Chun Liu, Jei Wei Chang
  • Publication number: 20020148105
    Abstract: A method for forming a bi-layer lift-off mask for use in fabricating an abutted junction type GMR read-head sensor with a narrow trackwidth of less than 0.5 microns. The mask has a novel suspension bridge structure that avoids problems associated with bi-layer lift-off masks of the prior art, namely insufficient or excessive undercutting of the lower layer that produces fence formations in the conducting lead layer or collapse of the mask structure rendering removal difficult.
    Type: Application
    Filed: April 16, 2001
    Publication date: October 17, 2002
    Applicant: Headway Technologies, Inc.
    Inventors: Cherng-Chyi Han, Rodney Lee, Mao-Min Chen, Pokang Wang
  • Patent number: 6466418
    Abstract: A method for forming a specularly reflecting bottom spin valve magnetoresistive (SVMR) sensor element with continuous spacer exchange hard bias and a specularly reflecting bottom spin valve magnetoresistive (SVMR) sensor element fabricated according to that method. To practice the method, there is provided a substrate upon which is formed a seed layer, upon which is formed an antiferromagnetic pinning layer, upon which is formed a ferromagnetic pinned layer, upon which is formed a non-magnetic spacer layer, upon which is formed a ferromagnetic free layer, upon which is formed a specularly reflecting and capping layer. The width of the sensor element is defined by a pair of conducting leads aligned upon a pair of continuous spacer exchange hard bias layers.
    Type: Grant
    Filed: February 11, 2000
    Date of Patent: October 15, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Cheng T. Horng, Min Li, Simon H. Liao, Ru-Ying Tong, Chyu Jiuh Torng, Rongfu Xiao
  • Patent number: 6460243
    Abstract: A method of making rhodium (Rh) lead layers for a read sensor comprises a first step of obliquely ion beam sputtering the rhodium (Rh) lead layer followed by a second step of annealing. This method results in rhodium (Rh) lead layers which have reduced stress and less resistance, making them highly desirable for lead layers of a sensor in a read head.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: October 8, 2002
    Assignee: International Business Machines Corporation
    Inventor: Mustafa Pinarbasi
  • Publication number: 20020135951
    Abstract: A lower electrode layer and a lower metallic layer are formed on a substrate, and a TMR multi-layer film is formed thereon. TMR multi-layer film is made up of a lower ferromagnetic layer, a tunnel barrier layer, an upper ferromagnetic layer, a pinning layer and a capping layer. In a region where a terminal is provided, a dummy lower electrode layer and a dummy lower metallic layer are formed on the substrate, and a dummy film is formed thereon. The dummy film has the same film composition as that of the TMR multi-layer film. For defining a shape of a tunnel joint, the capping layer through a halfway point in the lower ferromagnetic layer are selectively etched. In this etching process, the dummy film is also etched at the same time. In the etching process, a measurement for identifying elements scattered from the TMR multi-layer film and the dummy film is performed so as to control a position at which the etching is to be stopped.
    Type: Application
    Filed: January 10, 2002
    Publication date: September 26, 2002
    Applicant: TDK CORPORATION
    Inventors: Noriaki Kasahara, Takeo Kagami
  • Publication number: 20020135948
    Abstract: In a magnetoresistive effect element, at least one of electrodes for supplying a current perpendicularly to the film plane of a magnetoresistive effect film is narrower than the distance between bias-applying films. The sensitivity of the magnetoresistive effect film is lower in regions thereof near the bias-applying films due to an intensive bias magnetic field from the bias-applying films. However, the electrodes are disposed in an inner region having a high sensitivity avoiding those regions with a lower sensitivity to ensure a high sensitivity. The electrodes disposed on and under the magnetoresistive effect film are pillar-shaped to concentrate the sense current such that the sense current can be concentrically supplied exclusively to the region with the high sensitivity.
    Type: Application
    Filed: March 26, 2002
    Publication date: September 26, 2002
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomomi Funayama, Masayuki Takagishi, Kohichi Tateyama, Yuichi Ohsawa, Susumu Hashimoto, Michiko Hara, Akio Hori
  • Publication number: 20020131215
    Abstract: Magnetic tunnel junction (MTJ) and charge perpendicular-to-plane (CPP) magnetic sensors are disclosed which have a first antiferromagnetic layer for pinning the magnetization direction in a pinned layer and a second antiferromagnetic layer for providing bias stabilization of a free layer. The two antiferromagnetic layers may be formed from the same material and using a spin-flop effect may be initialized simulataneously. A disk drive using these sensors is disclosed.
    Type: Application
    Filed: March 14, 2001
    Publication date: September 19, 2002
    Inventor: Robert S. Beach
  • Patent number: 6452756
    Abstract: An object of the invention is to improve the insulating property between an electrode connected to a magnetoresistive element and a shield layer. A thin-film magnetic head of the invention includes: a magnetoresistive element; a bottom shield layer and a top shield layer for shielding the magnetoresistive element, wherein portions of the bottom shield layer and the top shield layer facing a recording medium are opposed to each other with the magnetoresistive element in between; two insulating layers each provided between the magnetoresistive element and each of the shield layers; a conductive layer connected to the magnetoresistive element; and an induction-type magnetic transducer. The bottom shield layer, for example, has a groove in which the conductive layer making up a lead connected to the magnetoresistive element is placed. The conductive layer is placed in the groove, being insulated by an insulating film from the bottom shield layer.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: September 17, 2002
    Assignee: TDK Corporation
    Inventor: Yoshitaka Sasaki
  • Patent number: 6447839
    Abstract: This invention is directed to methods for depositing multilayered thin films onto substrates, for example in making thin film magnetic heads. In accordance with the invention a first film, such as Cr, is deposited onto the substrate at a first pressure and a second layer, such as CoCrPt is deposited at a second pressure.
    Type: Grant
    Filed: June 26, 2000
    Date of Patent: September 10, 2002
    Assignee: Veeco Instruments, Inc.
    Inventors: Hari Hegde, Adrian Devasahayam, Jinsong Wang
  • Patent number: 6434814
    Abstract: A method of making a magnetic head that has a read head with a track width includes the steps of depositing a read track width defining material layer on a read sensor material layer; forming a bi-layer photoresist mask on the read track width defining material layer that masks a read track width defining layer portion of the read track width defining material layer; removing by reactive ion etching (RIE) a portion of the read track width defining material layer not masked by the photoresist mask to form the read track width defining layer portion with exposed first and second side edges that are spaced apart a distance equal to the track width; removing by ion milling a first portion of the read sensor material layer not masked by the read track width defining layer portion to form a second portion of the read sensor material layer with exposed first and second side edges that have a width equal to the track width; depositing hard bias and lead material layers on the photoresist mask in contact with the firs
    Type: Grant
    Filed: December 16, 1998
    Date of Patent: August 20, 2002
    Assignee: International Business Machines Corporation
    Inventors: Henry C. Chang, Cherngye Hwang, Robert Otto Schwenker
  • Patent number: 6430806
    Abstract: An inductive write element for use with a magnetic data recording and retrieval system is provided. The write element includes a magnetic yoke having an electrically conductive coil passing there through. The yoke is constructed of first and second magnetic poles, and performance of the write element is improved by the inclusion of a very thin pedestal of a high magnetic moment material on the first pole in the pole tip region. Further performance gains are realized by providing a tapered edge on the pedestal to facilitate magnetic flux flow through the pedestal.
    Type: Grant
    Filed: June 23, 2000
    Date of Patent: August 13, 2002
    Assignee: Read-Rite Corporation
    Inventors: Yingjian Chen, Ron Barr, Hua-Ching Tong, Stone Shi, Kyusik Sin
  • Patent number: 6427319
    Abstract: A method for protecting magnetic read/write head assembly against electrostatic discharge during disk drive manufacturing are disclosed. The magnetic head assembly is supported on a substrate having a magnetoresistive sensor element disposed in spaced relationship between several magnetic shield elements. Before a focused ion beam fabrication operation, at least a portion of an air bearing surface of the magnetic head assembly is coated with a thin and transparent layer of conductive material. This layer of conductive material is subsequent removed after the focused ion beam fabrication operation.
    Type: Grant
    Filed: May 15, 2000
    Date of Patent: August 6, 2002
    Assignee: International Business Machines Corporation
    Inventors: Jack Dana Cook, Grace Lim Gorman, Cherngye Hwang
  • Publication number: 20020089794
    Abstract: A read track width defining layer is employed for defining first and second side edges of a read sensor. The read track width defining layer preferably remains in the head to planarize the read head at first and second hard bias and lead layers so as to overcome a problem of write gap curvature in an accompanying write head. The read track width defining layer is defined by a subtractive process about a bilayer photoresist layer. The subtractive process is selective to the read track width defining layer over a read sensor material layer therebelow. Ion milling is then employed for defining first and second side edges of a read sensor layer employing the read track width defining layer as a mask. First and second hard bias and lead layers are then deposited which make contiguous junctions with the first and second side edges of each of the read sensor and read track width defining layers. The photoresist is then removed and the remainder of the read head is completed.
    Type: Application
    Filed: March 11, 2002
    Publication date: July 11, 2002
    Inventors: Henry C. Chang, Cherngye Hwang, Robert Otto Schwenker
  • Patent number: 6415500
    Abstract: Methods and structures are disclosed which avoid electrostatic charge build up and subsequent electrostatic discharge (ESD) during the wafer fabrication process of magnetoresistive (MR) or giant magnetoresistive (GMR) read/write heads of magnetic disk drives. This is achieved by designing the wafer layout and process so that the MR/GMR sensor film is shorted to the magnetic shields of the head through shorting paths so that there is an equal potential between MR/GMR sensor film and magnetic shields during the entire fabrication process.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: July 9, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Cherng-Chyi Han, Mao-Min Chen, Jen-Wei Koo, Rodney Lee, Li-Yan Zhu, Jei-Wei Chang
  • Publication number: 20020069511
    Abstract: In a method for manufacturing a magnetic field sensing element including an electrode layer overlying a second antiferrogmagnetic layer and a first free magnetic layer where the electrode layer exposes a portion of the second magnetic layer, a portion of the second antiferromagnetic layer not covered with the electrode layer and a portion of the first free magnetic layer are removed using the electrode layer as a mask after laminating each layer to form a bottom type spin-valve thin film magnetic element, thereby enabling the first free magnetic layer to be endowed with a sufficient exchange coupling magnetic field by substantially eliminating the tapered portion of the remaining second antiferromagnetic layer thereby enabling the magnetization of the second free magnetic layer to be put into a single domain state.
    Type: Application
    Filed: December 10, 2001
    Publication date: June 13, 2002
    Applicant: Alps Electric Co., Ltd.
    Inventors: Naoya Hasegawa, Eiji Umetsu, Masamichi Saito, Kenichi Tanaka, Yosuke Ide
  • Publication number: 20020067578
    Abstract: A method of forming a DSMR head comprises the steps of forming a first ferromagnetic (FM) strip on a substrate with a first anti-FM (AFM) pinning layer over a portion of the first ferromagnetic strip, the first AFM pinning layer being composed of a first material. Then perform a first high temperature annealing step. Form a non-magnetic layer over the strip and the pinning layer. Then form a second FM strip on the non-magnetic layer, and form a second AFM pinning layer over a portion of the second FM strip, with a second AFM pinning layer being composed identically of the first material. Perform a second high temperature annealing step on the first and second FM strips and the first and second pinning layers and the intermediate non-magnetic layer in the presence of a second magnetic field antiparallel to the first magnetic field. A head with NiFe FM strips and FeMn or MnPt, etc, AFM layers for both strips is provided.
    Type: Application
    Filed: September 6, 2001
    Publication date: June 6, 2002
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Simon H. Liao, Min Li
  • Patent number: 6399148
    Abstract: A lapping control sensor for a MR head includes a multi-layered structure of a metallic layer, an insulation layer, a resister layer and a lead conductor layer, and being provided in parallel with the MR head which has a multi-layered structure of at least a lower shield layer, a shield gap insulation layer, a MR layer and a lead conductor layer is provided. The insulation layer of the lapping control sensor has a thickness larger than that of the shield gap insulation layer of the MR head. The thickness of the insulation layer of the sensor is 0.1 &mgr;m or more.
    Type: Grant
    Filed: February 4, 2000
    Date of Patent: June 4, 2002
    Assignee: TDK Corporation
    Inventors: Osamu Fukuroi, Yoshiro Nakagawa
  • Patent number: 6396671
    Abstract: A spin valve structure, and method for manufacturing it, are described. The valve is subject to only small bias point shifts by sense current fields while at the same time has good GMR characteristics. This is achieved by introducing a layer of about 15 Angstroms of ruthenium between the seed layer and the free layer. This acts as an effective bias control layer with the added benefit of providing interfaces (to both the seed and the free layer) that are highly favorable to specular reflection of the conduction electrons. The HCP crystal structure of this ruthenium layer also improves the crystalline quality of the free layer thereby improving its performance with respect to the GMR ratio.
    Type: Grant
    Filed: March 15, 2000
    Date of Patent: May 28, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Cheng T. Horng, Mao-Min Chen, Kochan Ju, Min Li, Simon H. Liao, Ku-Ying Tong
  • Patent number: 6393692
    Abstract: A merged read/write magnetic recording head comprises a low magnetic moment first magnetic shield layer over a substrate. A read gap layer with a magnetoresistive head is formed over the first shield layer. A shared pole comprises a low magnetic moment second magnetic shield layer plated on a sputtered seed PLM layer over the read gap layer, a non-magnetic layer plated over the PLM layer and a HMM lower pole layer plated over the second magnetic shield layer. A write gap layer is formed over the first high magnetic moment pole layer of the shared pole. An upper pole comprises a high magnetic moment pole layer over the write gap layer.
    Type: Grant
    Filed: April 1, 1999
    Date of Patent: May 28, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Kochan Ju, Cherng-Chyi Han, Po-Kang Wang, Mao-Min Chen, Chun Liu, Jei-Wei Chang
  • Patent number: 6388847
    Abstract: A specular spin valve structure that is more robust than currently available specular spin valves is described. The improved stability is achieved by a using a modified pinned layer that is a laminate of three layers—a layer nickel-chromium, between about 3 and 4 Angstroms thick, sandwiched between two layers of cobalt-iron. A key requirement is that the cobalt-iron layer closest to the copper separation layer must be about twice as thick as the other cobalt-iron layer. A process for manufacturing this structure is also disclosed.
    Type: Grant
    Filed: February 1, 2000
    Date of Patent: May 14, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Cheng T. Horng, Min Li, Ru-Ying Tong, Rong-Fu Xiao
  • Publication number: 20020041465
    Abstract: It is an object of the invention to enable fine processing of not only a pole tip but a top pole layer to submicron measurement among the top pole which is divided into two. In the invention, the top pole is divided to the pole tip and the top pole layer, and a pole tip is formed on the flat surface of a bottom pole with a write gap layer in between. Through this, the pole tip which controls a recording track width is processed to submicron measurement. An insulating layer is formed in a region adjacent to the pole tip. A first layer of thin film coil is formed in a region where the insulating layer is formed. The thin film coil is covered by the insulating layer whose surface is flattened. As a result, difference in height of an apex area including a thin film coil becomes less for the size of (first layer of) thin film coil comparing to that of the related art. Accordingly, an effect of difference in height of the apex area is decreased when the top pole layer is formed by photolithography.
    Type: Application
    Filed: December 6, 2001
    Publication date: April 11, 2002
    Applicant: TDK Corporation
    Inventor: Yoshitaka Sasaki
  • Publication number: 20020036876
    Abstract: The invention increases the electric resistance of CPP-GMR elements to a practical range. Moreover, the invention presents a CPP-GMR element and a TMR element that can be applied to track widths that are made narrower due to higher densities of the magnetic recording. The area S1 of a non-magnetic layer 7 is 1 &mgr;m or less, and at least one layer selected from a first magnetic layer 6, a second magnetic layer 8 and the non-magnetic layer 7 includes a first region 30 through which current flows and a second region 20 made of an oxide, a nitride or an oxynitride of the film constituting that first region. The area S2 of the first region is smaller than the area of the non-magnetic layer. At least one of the layers of the element is oxidized, nitrided or oxynitrided from a lateral side.
    Type: Application
    Filed: September 4, 2001
    Publication date: March 28, 2002
    Inventors: Yasuhiro Kawawake, Yasunari Sugita, Akihiro Odagawa, Akihisa Yoshida, Hiroshi Sakakima
  • Publication number: 20020029463
    Abstract: During a process of manufacturing a spin valve film which produces a large read out signal upon being used as a reading element of a thin film magnetic head, after a completion of a film making process for forming a previous film of two films to be formed successively, but before an initiation of a film making process for forming a succeeding film of the two films, a step of decreasing an anisotropic magnetic field of the spin valve film by interrupting a film making process is introduced. The anisotropic magnetic field reducing step may be performed by keeping a substrate within a sputtering vacuum chamber.
    Type: Application
    Filed: March 28, 2001
    Publication date: March 14, 2002
    Applicant: TDK CORPORATION
    Inventors: Hajime Amano, Hiroaki Takezutsumi, Tetsuro Sasaki, Jun-Ichi Sato
  • Publication number: 20020030950
    Abstract: Provided are a magnetic transducer and a thin film magnetic head having good thermal stability and capable of obtaining a high exchange coupling magnetic field, a method of manufacturing a magnetic transducer and a method of a manufacturing a thin film magnetic head. An MR element has a stack having a stacked structure comprising an underlayer, a crystal-growth inhibitor layer, a first soft magnetic layer, a second soft magnetic layer, a nonmagnetic layer, a ferromagnetic layer, an antiferromagnetic layer and a cap layer, which are stacked in sequence. The ferromagnetic layer has an inner ferromagnetic layer, a coupling layer and an outer ferromagnetic layer, which are stacked in this order on the nonmagnetic layer.
    Type: Application
    Filed: July 16, 2001
    Publication date: March 14, 2002
    Applicant: TDK CORPORATION
    Inventors: Masashi Sano, Satoru Araki, Yoshihiro Tsuchiya, Takumi Uesugi
  • Patent number: 6353995
    Abstract: A insulating layer having a opening corresponding to a bottom pole tip is formed on a bottom pole layer. The insulating layer is made of a insulating material such as alumina and formed by, for example, sputtering or CVD. On the insulating layer and the bottom pole layer, a magnetic layer is formed. Subsequently, the magnetic layer is planarized to expose the surface of the insulating layer by CMP (Chemical and Mechanical Polishing). By this step, a bottom pole tip adjacent to the insulating layer is formed on the bottom pole layer. Using this method, it is easy to manufacture a structure that the magnetic pole and the insulating layer lie contiguously and a throat height of a recording head is determined precisely.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: March 12, 2002
    Assignee: TDK Corporation
    Inventors: Yoshitaka Sasaki, Atsushi Iijima
  • Publication number: 20020027754
    Abstract: The present invention is a magnetoresistive (MR) sensor (100) that combines the advantages of abutted junction structure and regular overlaid structure. The abutted junction design is used with the soft adjacent layer (SAL) (108) and the overlaid structure is used with the MR element (120). The method of making the MR sensor (100) comprises depositing SAL (108) on top of the gap layer (106) and depositing spacer material (110) on top of the SAL (108). A mask (130) is placed over the central region of the spacer material (110) and SAL (108). The spacer material (110) and SAL (108) are removed in the areas not covered by the mask (130). An underlayer material (112) is deposited in the areas where the SAL (108) and spacer material (110) were removed. A hard-biasing material (114) is deposited on top of the underlayer (112).
    Type: Application
    Filed: November 6, 1998
    Publication date: March 7, 2002
    Inventors: JUREN DING, SONG SHENG XUE, JUAN FERNANDEZ-DECASTRO, JAMES DOLEJSI, PATRICK JOSEPH RYAN
  • Publication number: 20020026705
    Abstract: In the present invention a second pole yoke component of a second pole piece is connected (stitched) to a small top surface of a second pole tip component of the second pole piece as well as to a back edge and first and second side edges of the second pole tip component. The extra stitching at the back and side edges provides the required magnetic coupling between the components for transferring flux to and from a second pole tip at an air bearing surface. This arrangement shortens the length of the top stitched area so that one or more coil layers in an insulation stack can be located closer to the ABS for increasing the data rate of the head. Further, this arrangement reduces the amount of material of the second pole piece layer in close proximity to the first pole piece layer so as to minimize flux leakage therebetween.
    Type: Application
    Filed: August 17, 2001
    Publication date: March 7, 2002
    Inventor: Hugo Alberto Emilio Santini
  • Patent number: 6345435
    Abstract: A method and design for the fabrication of a laminated yoke for a high data rate magnetic read-write transducer head. A full film layer of first ferromagnetic material is formed on a base using either plating or sputtering. The base comprises a read head, a ferromagnetic pole piece, and a ferromagnetic shield which also serves as a pole piece. A patterned layer of first non-magnetic dielectric is then formed on the full film layer of first ferromagnetic material. A patterned layer of photoresist is then formed on the full film layer of first ferromagnetic material and the patterned non-magnetic dielectric and used as a frame for a frame plating deposition of a patterned layer of second ferromagnetic material. The full film layer of first ferromagnetic material and the non-magnetic dielectric are then patterned, using the patterned layer of second ferromagnetic material as a mask and ion beam etching.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: February 12, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Cherng-Chyi Han, Chyu-Jiuh Torng, Rodney Lee, Kochan Ju
  • Publication number: 20020013995
    Abstract: After forming a bottom shield layer on a substrate, a GMR element embedded within a shield gap layer is formed. After forming a write gap layer on a first magnetic layer and an inorganic insulating layer, a second magnetic layer is formed to have a pole portion within a cut-out portion of the inorganic insulating layer and a connecting portion extending above the inorganic insulating layer. A third magnetic layer is formed that makes contact not only with a surface of the pole portion of the second magnetic layer but also with side walls of the pole portion. The thin film magnetic head has a narrow pole chip defining a track width, although the throat height is small, saturation and leakage of a magnetic flux can be suppressed, thin film magnetic head having a high recording efficiency can be manufactured with a high yield.
    Type: Application
    Filed: October 9, 2001
    Publication date: February 7, 2002
    Applicant: TDK Corporation
    Inventor: Yoshitaka Sasaki
  • Publication number: 20020007551
    Abstract: The invention allows a thin-film magnetic head that meets specifications required by the customer to be provided in a short period of time and manufacturing costs to be reduced. A slider of a magnetic head of the invention comprises two thin-film magnetic head element portions formed near an end face orthogonal to the direction of air flow. On the end face four pad-shaped electrodes are provided for electrically connecting the two head element portions to an external device. The electrodes are selectively connected to one of the head element portions through four conductors.
    Type: Application
    Filed: October 4, 2001
    Publication date: January 24, 2002
    Applicant: TDK CORPORATION
    Inventor: Yoshitaka Sasaki
  • Patent number: 6339872
    Abstract: A single-sided, notched write head is provided for writing narrow erase band servo tracks as well as a double-notched write head, and for writing data tracks better than a double-notched write head. The single-sided, notched write head writes a narrow erase band on the notched side and a wide erase band on the unnotched side. In one embodiment, only one side of the first pole piece layer is notched, and in another embodiment a first side of the first pole piece layer is notched more than a second side. By writing servo tracks only a fraction of the track width of the write head, a wide erase band region is overwritten so that a narrow erase band is on each side of the servo track. Data tracks are written with a narrow erase band on one side and a wide erase band on the other side. The wide erase band on one side of the data track allows more flexibility in spacing the read head from adjacent tracks.
    Type: Grant
    Filed: May 3, 2000
    Date of Patent: January 22, 2002
    Assignee: International Business Machines Corporation
    Inventors: Thomas Young Chang, Edward Hinpong Lee, Jyh-Shuey Jerry Lo
  • Publication number: 20020006020
    Abstract: Insulating layers are formed on both sides of a multilayer film, and bias layers are formed in contact with at least portions of both end surfaces of a free magnetic layer. The bias layers are formed so as not to extend to the upper surface of the multilayer film. In this construction, a sensing current from electrode layers appropriately flows through the multilayer film, and a bias magnetic field can be supplied to the free magnetic layer from the bias layers through both side surfaces of the free magnetic layer. Furthermore, the magnetic domain structure of the free magnetic layer can be stabilized to permit an attempt to decrease instability of the reproduced waveform and Barkhausen noise.
    Type: Application
    Filed: July 13, 2001
    Publication date: January 17, 2002
    Applicant: Alps Electric Co., Ltd.
    Inventor: Naoya Hasegawa
  • Publication number: 20020006017
    Abstract: A magnetoresistive angular sensor (1) is provided which determines a magnetic field direction. A high angular accuracy over a wide range of magnetic field strengths is obtained. The magnetoresistive angular sensor comprises a main sensing element (2) which is electrically connected to a first correction sensing element (6) with a first reference magnetization axis (9) and a second correction sensing element (8) with a second reference magnetization axis (10), the first (9) and the second (10) reference magnetization axes making correction angles &THgr; between 5° and 85° of opposite sign with the main reference axis (3).
    Type: Application
    Filed: May 24, 2001
    Publication date: January 17, 2002
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventor: Derk Jan Adelerhof
  • Publication number: 20020006021
    Abstract: A multilayer structure is described having an antiferromagnetic layer between a first and second layer. The antiferromagnetic layer has antiferromagnetic coupling that helps pin the magnetization direction of the first layer and helps pin the magnetization direction of the second layer.
    Type: Application
    Filed: April 4, 2001
    Publication date: January 17, 2002
    Inventor: Robert S. Beach
  • Patent number: 6338939
    Abstract: A read/write head is provided with an embedded planar dual coil write structure. The head includes generally parallel shield, shield/pole, and pole layers. The shield/pole layer abuts a generally coplanar planarization layer in one embodiment. A circuitous recess is defined in the shield/pole and planarization layer, spanning the junction twice and encircling a central hub of adjoining shield/pole and planarization layer material. A write structure is located in the recess, with the shield/pole layer, planarization layer, and embedded write structure forming a substantially flat surface for building the pole layer. The write structure includes first and second substantially co-planar multi-turn flat coils, where turns of the first write coil are interspersed with turns of the second write coil. The first and second write coils reside in the circuitous recess, winding around the central hub. An insulating material separates the first and second coils.
    Type: Grant
    Filed: August 24, 2000
    Date of Patent: January 15, 2002
    Assignee: International Business Machines Corporation
    Inventors: Thomas Carl Clarke, Robert Edward Fontana, Jr., Richard Hsiao, Eric James Lee, Hugo Alberto Emilio Santini
  • Publication number: 20010055185
    Abstract: A spin-valve thin-film magnetic element includes a laminate formed on a substrate, the laminate including an antiferromagnetic layer, a pinned magnetic layer in contact with the antiferromagnetic layer, a nonmagnetic conductive layer in contact with the pinned magnetic layer, and a free magnetic layer in contact with the nonmagnetic conductive layer; bias layers formed on both sides in the track-width direction of the laminate; and electrode layers formed on the bias layers. The bias layers are in contact with both sides of the laminate and extend over the peripheral sections of the laminate with ferromagnetic bias underlying layers therebetween, the bias underlying layers being composed of Fe or an Fe-Co alloy with a thickness of 1.6 to 4.3 nm. A method for fabricating a spin-valve thin-film magnetic element is also disclosed.
    Type: Application
    Filed: June 14, 2001
    Publication date: December 27, 2001
    Applicant: Alps Electric Co., Ltd.
    Inventors: Masahiro Ooshima, Naoya Hasegawa
  • Patent number: 6330743
    Abstract: In order to provide a thin film magnetic head having a high performance as well as a method of manufacturing the same, in which throat height TH of a pole portion and MR height MRH can be formed accurately to have desired design values for improving a surface recording density and reducing a side fringe magnetic flux during a writing, after forming a MR element on a substrate 41, 42, a first magnetic film 47 is formed on the MR element, a write gap layer 48 is deposited on the first magnetic layer, a thin film coil 50, 52 supported by a coil supporting insulating layer 51, 53 is formed, a second magnetic layer 54 is formed on the insulating layer, non-magnetic side walls 55a are selectively formed on side surfaces of a pole portion of the second magnetic layer, a part of the write gap layer in the vicinity of the pole portion and a part of the first magnetic layer are selectively removed by anisotropic etching to form a recess 56 while said pole portion and side walls are used as a mask.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: December 18, 2001
    Assignee: TDK Corporation
    Inventors: Atsushi Iijima, Yoshitaka Sasaki
  • Patent number: 6330127
    Abstract: A thin-film magnetic head and a method of manufacturing the same in which a precise control of a pole width can be performed and, at the same time, a sufficient overwrite characteristic can be obtained is provided. A top pole includes a top area defining a track width, a middle area coupled to the top area and a yolk area coupled to the middle area. Positions of the coupling point of the middle area and the top area are met with throat height 0 position which is a reference point of throat height. In the coupling point, a step in the width direction with almost a right angle is provided. A width of the middle area is made sufficiently wider than a width of the top area in the coupling point. Widening a pattern width of photoresist for forming the top area can be prevented and micronizing a recording track width is made possible.
    Type: Grant
    Filed: November 16, 1998
    Date of Patent: December 11, 2001
    Assignee: TDK Corporation
    Inventor: Yoshitaka Sasaki
  • Patent number: 6325947
    Abstract: A method for forming a merged thin film magnetic head having a first shield layer and a combined second shield and bottom pole piece layer arranged in a sandwich supporting a read sensor therebetween at the pole tip region. The combined second shield and bottom pole piece layer are magnetically coupled with the first shield layer at the pole tip end of the yoke region adjacent the read sensor, and overlaying and magnetically coupled with the first shield layer at the back gap region. A patterned opening is provided in the combined second shield and bottom pole piece layer at the yoke region thereof to expose the first shield layer and form a flat planarization surface thereon. A plurality of stacked thin film coil layers are provided in the patterned opening, and a top pole piece layer overlies the thin film coil at the yoke region, overlies the bottom pole piece at the pole tip region providing a pole tip and gap thereat, and overlies the bottom pole piece at the back gap region.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: December 4, 2001
    Assignee: International Business Machines Corporation
    Inventors: Glen Adam Garfunkel, Edward Hinpong Lee, Joseph Francis Smyth, Samuel Wonder Yuan
  • Patent number: 6325900
    Abstract: A magnetic sensor utilizing a spin tunnel magneto-resistance effect (TMR), comprising a tunnel insulating film, a first magnetic layer formed on one of the planes of the tunnel insulating film, a second magnetic layer formed on the other plane of the tunnel insulating film, a third magnetic layer containing an anti-ferromagnetic substance for fixing magnetization of the second magnetic layer, a second insulating film formed on at least one of the first and third magnetic layers and having an opening in a predetermined region, a first electrode electrically connected to one of the first and third magnetic layers only in the opening of the second insulating film, and a second electrode for causing a current to flow between the first electrode and itself through at least the first and second magnetic layers and the first insulating layer.
    Type: Grant
    Filed: August 30, 2000
    Date of Patent: December 4, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Matahiro Komuro, Yoshiaki Kawato
  • Publication number: 20010043445
    Abstract: A thin film magnetic head includes: a lower magnetic pole (8); an upper magnetic pole (16) disposed to face the lower magnetic pole; a recording coil disposed between the lower magnetic pole and the upper magnetic pole, the recording coil being spaced from the both magnetic poles; and an upper tip sub-magnetic pole (22) provided at the side of the lower magnetic pole of the upper magnetic pole in the vicinity of a floating surface (ABS). In the first aspect, the upper magnetic pole and the upper tip sub-magnetic pole are disposed in such a manner that an end portion at the side of the floating surface of the upper magnetic pole recedes from an end portion at the side of the floating surface of the upper tip sub-magnetic pole. In the second aspect, a portion of the upper magnetic pole in the vicinity of the floating surface is formed to be narrower than the other portion of the pole, and to be wider than a core width of the upper tip sub-magnetic pole.
    Type: Application
    Filed: March 9, 2001
    Publication date: November 22, 2001
    Applicant: FUJITSU LIMITED
    Inventors: Syuji Nishida, Ikuya Tagawa, Tomoko Kutsuzawa