公开(公告)号：US20050227122A1

公开(公告)日：2005-10-13

申请号：US10511584

申请日：2003-03-20

Applicant: Migaku Takahashi ,  David Djayaprawira ,  Hirold Domon

Inventor： Migaku Takahashi ,  David Djayaprawira ,  Hirold Domon

IPC: C23C14/14 ,  G11B5/64 ,  G11B5/65 ,  G11B5/66 ,  G11B5/673 ,  G11B5/73 ,  G11B5/738 ,  G11B5/84 ,  H01F10/16

CPC classification number: G11B5/7325 ,  G11B5/66 ,  G11B5/7379

Abstract: A vertical magnetic recording medium exhibiting excellent noise characteristics in which magnetic interaction is reduced in a magnetic layer. The vertical magnetic recording medium (10) includes a nonmagnetic substrate (1), an underlying layer (2) formed directly or indirectly on the nonmagnetic substrate (1), and a magnetic layer (4) for recording magnetic information formed on the underlying layer (2), characterized in that the underlying layer (2) is composed of an alloy principally including two kinds of element, difference of standard free energy ΔG° for producing an oxide or a nitride of the both elements at room temperature is set not lower than 70 kJ/mol[O2 or N2], and crystal grains constituting the underlying layer (2) principally includes one of two elements having a higher ΔG°, and the grain boundary of the underlying layer (2) principally includes an oxide or a nitride of an element having a lower ΔG°.

Abstract translation: 具有优异的噪声特性的垂直磁记录介质，其磁性层中的磁相互作用减小。 垂直磁记录介质（10）包括非磁性衬底（1），直接或间接形成在非磁性衬底（1）上的下层（2）和用于记录形成在下层上的磁信息的磁性层（4） （2），其特征在于，下层（2）由主要包含两种元素的合金构成，室温下用于制造两种元素的氧化物或氮化物的标准自由能差ΔG°的差设定为不低 构成下层（2）的晶粒主要包括具有较高ΔG°的两个元素中的一个，并且下层（2）的晶界主要包括氧化物或 具有较低DeltaG°的元素的氮化物。

公开(公告)号：US20050158585A1

公开(公告)日：2005-07-21

申请号：US10509244

申请日：2003-03-20

Applicant: Migaku Takahashi ,  Shin Saito ,  David Djayaprawira

Inventor： Migaku Takahashi ,  Shin Saito ,  David Djayaprawira

IPC: B32B15/01 ,  C22C38/02 ,  C22C38/06 ,  C23C28/00 ,  G11B5/66 ,  G11B5/667 ,  G11B5/73 ,  G11B5/84 ,  G11B5/851 ,  H01F10/14 ,  H01F41/14 ,  B05D5/12

CPC classification number: C22C38/02 ,  B32B15/01 ,  C22C38/06 ,  C23C28/321 ,  C23C28/34 ,  C23C28/343 ,  C23C28/347 ,  G11B5/66 ,  G11B5/667 ,  G11B5/8404 ,  G11B5/851 ,  Y10T428/265

Abstract: A vertical magnetic recording medium has a low-noise characteristic compared to media of a permalloy or sendust crystalline material, including a high-flatness soft magnetic backing layer, and enabling recording/reproduction of information at high recording density, a magnetic recorder provided with the vertical magnetic recording medium, a vertical magnetic recording medium manufacturing method and apparatus. The vertical magnetic recording medium has a multilayer structure on a substrate, in which a soft magnetic backing layer, a vertical recording layer of a ferromagnetic body, and a protective layer are formed. The soft magnetic backing layer is formed of an FeSiAlN film of a soft magnetic material. The atom % of each element of Fe, Si, Al, and N of the FeSiAlN film can be changed by changing the flow rate of N2 gas in a mixture gas of N2 gas and Ar gas introduced into the chamber.

Abstract translation: 垂直磁记录介质与坡莫合金或铁硅铝结晶材料的介质相比具有低噪声特性，包括高平坦度软磁背衬层，并且能够以高记录密度记录/再现信息，磁记录器具有 垂直磁记录介质，垂直磁记录介质制造方法和装置。 垂直磁记录介质在其上形成软磁背衬层，铁磁体垂直记录层和保护层的基板上具有多层结构。 软磁背衬层由软磁材料的FeSiAlN膜形成。 FeSiAlN膜的Fe，Si，Al和N的各元素的原子％可以通过改变引入到室中的N 2气体和Ar气体的混合气体中的N 2气体的流量来改变。

公开(公告)号：US06841259B1

公开(公告)日：2005-01-11

申请号：US09720736

申请日：2000-11-20

Applicant: Migaku Takahashi ,  David Djayaprawira ,  Hiroki Shoji

Inventor： Migaku Takahashi ,  David Djayaprawira ,  Hiroki Shoji

IPC: G11B5/00 ,  G11B5/127 ,  G11B5/31 ,  G11B5/39 ,  G11B5/66 ,  G11B5/667 ,  G11B5/73 ,  H01F10/14 ,  H01F10/18 ,  H01F10/32 ,  H01F17/00 ,  H01P3/08 ,  B32B15/04 ,  H01R10/10 ,  H01R10/14

CPC classification number: H01P3/088 ,  B82Y10/00 ,  B82Y25/00 ,  G11B5/00 ,  G11B5/1278 ,  G11B5/3109 ,  G11B5/3143 ,  G11B5/3909 ,  G11B5/3967 ,  G11B5/66 ,  G11B5/7325 ,  G11B2005/0002 ,  G11B2005/3996 ,  H01F10/14 ,  H01F10/18 ,  H01F10/3222 ,  H01F10/324 ,  H01F10/3286 ,  H01F17/0033 ,  Y10T428/115

Abstract: A magnetic thin film with a saturation magnetic flux density of 2 T or more and a coercive force of 2 Oe or less for a magnetic pole material of a recording head. The magnetic thin film consists of an iron carbide film that includes a martensite (α′) phase as the principal phase and at least carbon and iron as constituent elements. The iron carbide film preferably consists of a single α′ phase. The iron carbide film has a body-centered tetragonal structure and a c-axis constitutes an axis of hard magnetization and, a c-plane constitutes a plane of easy magnetization. The axis of hard magnetization constitutes a direction which is generally perpendicular to the film surface, and the plane of easy magnetization constitutes a direction which is generally parallel to the film surface.

Abstract translation: 对于记录头的磁极材料，具有2T以上的饱和磁通密度和2Oe以下的矫顽力的磁性薄膜。 磁性薄膜由包含马氏体（α'）相作为主相的碳化铁膜和至少碳和铁作为组成元素组成。 碳化铁膜优选由单个α'相组成。 碳化铁膜具有体心四方结构，c轴构成硬磁化轴，c面构成容易磁化的平面。 硬磁化轴构成大致垂直于膜表面的方向，容易磁化的平面构成大致平行于膜表面的方向。

公开(公告)号：US20050214584A1

公开(公告)日：2005-09-29

申请号：US10509616

申请日：2003-03-20

Applicant: Migaku Takahashi ,  David Djayaprawira ,  Hiroki Domon ,  Satoru Yoshimura

Inventor： Migaku Takahashi ,  David Djayaprawira ,  Hiroki Domon ,  Satoru Yoshimura

IPC: G11B5/64 ,  G11B5/66 ,  G11B5/673 ,  G11B5/738 ,  G11B5/84 ,  G11B5/851 ,  B05D5/12

CPC classification number: G11B5/851 ,  G11B5/66

Abstract: A method for producing a magnetic recording medium having a flat surface and a strong exchange bias field, and excellent in thermal stability. The method for producing a magnetic recording medium related to the present invention comprising a nonmagnetic substrate 1, a metal underlayer 2, and a ferromagnetic metal layer 3 formed successively in multilayer. The method comprises a step of forming the ferromagnetic layer 3 where ferromagnetic films 3a, 3b and one or more nonmagnetic metal spacer layer 4 are alternately formed in a multilayer and a step of allowing at least the interface of the nonmagnetic metal spacer layers 4 to physically adsorb oxygen and/or nitrogen.

Abstract translation: 一种具有平坦表面和强交换偏磁场的磁记录介质的制造方法，其热稳定性优异。 本发明涉及的磁记录介质的制造方法，其特征在于，包括依次层叠形成的非磁性基板1，金属底层2和强磁性金属层3。 该方法包括形成强磁性层3的步骤，其中铁磁膜3a，3b和一个或多个非磁性金属间隔层4在多层中交替形成，并且至少允许非磁性金属间隔层4的界面 物理吸附氧气和/或氮气。

公开(公告)号：US06709775B1

公开(公告)日：2004-03-23

申请号：US09979851

申请日：2001-11-28

Applicant: Migaku Takahashi ,  Satoru Yoshimura ,  David Djayaprawira ,  Hiroki Shoji

Inventor： Migaku Takahashi ,  Satoru Yoshimura ,  David Djayaprawira ,  Hiroki Shoji

IPC: G11B566

CPC classification number: G11B5/732 ,  G11B5/7325 ,  G11B5/8404 ,  Y10S428/90 ,  Y10T428/12465 ,  Y10T428/12854

Abstract: A magnetic recording medium capable of suppressing the effects of thermal agitation and simultaneously reducing the average grain diameter and the standard deviation of magnetic crystal grains constituting a ferromagnetic metal film, without changing the film thickness of a metal under-layer or the film thickness of a ferromagnetic metal layer forming a recording layer, as well as a production method thereof, and a magnetic recording device. The magnetic recording medium includes a ferromagnetic metal layer of a cobalt based alloy formed on a base material with a metal underlayer having chromium as a major constituent disposed there between, wherein a seed layer having at least tungsten is provided between the base material and the metal under-layer, and the seed layer is an islands type film.

Abstract translation: 一种能够抑制热搅拌的影响并同时降低构成铁磁性金属膜的磁性晶粒的平均粒径和标准偏差的磁记录介质，而不改变金属底层的膜厚度或膜厚度 形成记录层的铁磁性金属层及其制造方法以及磁记录装置。 磁记录介质包括在基材上形成的钴基合金的强磁性金属层，其中具有设置在其间的主要成分为铬的金属底层，其中至少具有钨的种子层设置在基材和金属之间 底层，种子层是岛状膜。

公开(公告)号：US06878459B2

公开(公告)日：2005-04-12

申请号：US10026709

申请日：2001-12-27

Applicant: Migaku Takahashi ,  David Djayaprawira ,  Kazuya Komiyama ,  Satoru Yoshimura

Inventor： Migaku Takahashi ,  David Djayaprawira ,  Kazuya Komiyama ,  Satoru Yoshimura

IPC: C23C14/14 ,  G11B5/64 ,  G11B5/65 ,  G11B5/73 ,  G11B5/738 ,  G11B5/84 ,  G11B5/851 ,  G11B5/66

CPC classification number: G11B5/7325 ,  G11B5/656 ,  Y10T428/12639 ,  Y10T428/12833 ,  Y10T428/12847 ,  Y10T428/12861 ,  Y10T428/12986 ,  Y10T428/24967 ,  Y10T428/24975 ,  Y10T428/265 ,  Y10T428/31

Abstract: A magnetic recording medium was a high normalized coercive force and superior thermal stability. The magnetic recording medium comprises a non-magnetic base material, and a ferromagnetic metal layer of cobalt based alloy formed on top of this base material with a metal underlayer disposed therebetween, and displays a coercive force Hc of at least 2000 (Oe) and an anisotropic magnetic field Hkgrain of at least 10,000 (Oe). Furthermore, magnetic recording media in which the aforementioned metal underlayer and/or the ferromagnetic metal layer are fabricated in a film fabrication chamber with an ultimate vacuum at the 10−9 Torr level are preferred. A magnetic recording medium according to the present invention can be ideally applied to hard disks, floppy disks, and magnetic tapes and the like.

Abstract translation: 磁记录介质是高归一化矫顽力和优异的热稳定性。 磁记录介质包括非磁性基材，以及形成在该基材顶部上的钴基合金的强磁性金属层，其间设置有金属底层，并显示出至少2000（Oe）的矫顽力Hc和 至少10,000（Oe）的各向异性磁场Hk <颗粒>。 此外，优选在具有10 -9乇级别的极限真空的膜制造室中制造上述金属底层和/或强磁性金属层的磁记录介质。 根据本发明的磁记录介质可以理想地应用于硬盘，软盘和磁带等。

公开(公告)号：US20140001398A1

公开(公告)日：2014-01-02

申请号：US13980703

申请日：2012-01-19

Applicant: Migaku Takahashi ,  Tomoyuki Ogawa ,  Yasunobu Ogata ,  Naoya Kobayashi ,  Chammika Ruwan Polwatta Gallage ,  Kaori Kohara

Inventor： Migaku Takahashi ,  Tomoyuki Ogawa ,  Yasunobu Ogata ,  Naoya Kobayashi ,  Chammika Ruwan Polwatta Gallage ,  Kaori Kohara

IPC: H01F1/01 ,  H01F41/00

CPC classification number: H01F1/01 ,  B22F1/02 ,  B22F9/22 ,  B22F2999/00 ,  C01B21/0622 ,  C01P2004/54 ,  C01P2004/61 ,  C01P2006/12 ,  C01P2006/42 ,  C22C21/00 ,  C22C29/16 ,  H01F1/065 ,  H01F1/083 ,  H01F1/086 ,  H01F41/00 ,  H01F41/0266 ,  B22F2201/013

Abstract: The present invention relates to ferromagnetic particles capable of exhibiting a high purity and excellent magnetic properties from the industrial viewpoints and a process for producing the ferromagnetic particles, and also provides an anisotropic magnet, a bonded magnet and a compacted magnet which are obtained by using the ferromagnetic particles. The ferromagnetic particles comprising an Fe16N2 compound phase in an amount of not less than 80% as measured by Mössbauer spectrum and each having an outer shell in which FeO is present in the form of a film having a thickness of not more than 5 nm according to the present invention can be produced by subjecting iron oxide or iron oxyhydroxide having an average major axis diameter of 40 to 5000 nm and an aspect ratio (major axis diameter/minor axis diameter) of 1 to 200 as a starting material to dispersing treatment to prepare aggregated particles; subjecting the iron compound particles passed through a mesh to hydrogen reducing treatment at a temperature of 160 to 420° C.; and then subjecting the resulting particles to nitridation treatment at a temperature of 130 to 170° C.

Abstract translation: 本发明涉及从工业观点出发具有高纯度和优异磁特性的铁磁性颗粒以及制造铁磁性颗粒的方法，并且还提供了各向异性磁体，粘结磁体和压实磁体，它们通过使用 铁磁颗粒。 所述铁磁性粒子包含通过Mössbauer光谱测定的不小于80％的Fe 16 N 2化合物相，并且每个具有外壳，其中FeO以厚度不超过5nm的膜的形式存在，根据 本发明可以通过使平均长轴直径为40〜5000nm，长径比（长轴径/短轴直径）为1〜200的氧化铁或羟基氧化铁作为起始原料进行分散处理而制备 聚集颗粒; 使通过网的铁化合物颗粒在160〜420℃的温度下进行氢还原处理。 然后在130〜170℃的温度下对得到的粒子进行氮化处理。

公开(公告)号：US08154828B2

公开(公告)日：2012-04-10

申请号：US12500835

申请日：2009-07-10

Applicant: Yoshihiro Tsuchiya ,  Shinji Hara ,  Kiyoshi Noguchi ,  Migaku Takahashi ,  Masakiyo Tsunoda

Inventor： Yoshihiro Tsuchiya ,  Shinji Hara ,  Kiyoshi Noguchi ,  Migaku Takahashi ,  Masakiyo Tsunoda

IPC: G11B5/39

CPC classification number: G11B5/3929 ,  B82Y10/00 ,  B82Y25/00 ,  G11B2005/3996

Abstract: An MR element in a CPP structure includes a spacer layer made of Cu, a magnetic pinned layer containing CoFe and a free layer containing CoFe that are laminated to sandwich the spacer layer. The free layer is located below the magnetic pinned layer. The free layer is oriented in a (001) crystal plane, the spacer layer is formed and oriented in a (001) crystal plane on the (001) crystal plane of the free layer. Therefore, in a low resistance area where an area resistivity (AR) of the MR element is, for example, lower than 0.3 Ω·μm2, an MR element that has a large variation of a resistance is obtained.

Abstract translation: CPP结构中的MR元件包括由Cu制成的间隔层，包含CoFe的磁性固定层和层压以夹持间隔层的CoFe的自由层。 自由层位于磁性固定层的下方。 自由层在（001）晶面取向，间隔层形成并定向在自由层的（001）晶面上的（001）晶面上。 因此，在MR元件的面积电阻率（AR）例如低于0.3

公开(公告)号：US08034471B2

公开(公告)日：2011-10-11

申请号：US12536225

申请日：2009-08-05

Applicant: Shinichi Ishibashi ,  Migaku Takahashi ,  Shin Saito ,  Yuzo Sasaki ,  Atsushi Hashimoto ,  Gohei Kurokawa ,  Tomoyuki Maeda ,  Akihiko Takeo

Inventor： Shinichi Ishibashi ,  Migaku Takahashi ,  Shin Saito ,  Yuzo Sasaki ,  Atsushi Hashimoto ,  Gohei Kurokawa ,  Tomoyuki Maeda ,  Akihiko Takeo

IPC: G11B5/66

CPC classification number: G11B5/82 ,  G11B5/65 ,  G11B5/667 ,  G11B5/732

Abstract: In a perpendicular magnetic recording medium in which at least a soft magnetic underlayer, an orientation control layer, a magnetic recording layer and a protective layer are formed on a non-magnetic substrate in order from the bottom, the orientation control layer has a laminated structure of two or more layers including an intermediate layer and a seed layer which is disposed closer to the non-magnetic substrate than the intermediate layer. The seed layer includes two or more kinds of elements having a face-centered cubic structure, has face-centered cubic (111) plane crystals oriented in a direction perpendicular to a substrate surface, and has a pseudo-hexagonal structure.

Abstract translation: 在从底部起依次形成至少软磁性底层，取向控制层，磁记录层和保护层的垂直磁记录介质中，取向控制层具有层叠结构 包括比中间层更靠近非磁性基板设置的中间层和种子层的两层以上的层。 种子层包括具有面心立方结构的两种或更多种元件，具有在垂直于衬底表面的方向上取向的面心立方（111）面晶体，并且具有假六边形结构。

公开(公告)号：US07862915B2

公开(公告)日：2011-01-04

申请号：US11640979

申请日：2006-12-19

Applicant: Tomoyuki Maeda ,  Migaku Takahashi ,  Masahiro Oka

Inventor： Tomoyuki Maeda ,  Migaku Takahashi ,  Masahiro Oka

IPC: G11B5/65

CPC classification number: G11B5/7325 ,  G11B5/1278 ,  G11B5/82

Abstract: According to one embodiment, a multilayered underlayer including a first underlayer containing Cu aligned in a (111) plane and a second underlayer formed on the Cu underlayer and containing Cu and nitrogen as main components is formed.

Abstract translation: 根据一个实施方案，形成包含在（111）面中排列的Cu的第一底层和形成在Cu底层上并含有Cu和氮作为主要成分的第二底层的多层底层。