公开(公告)号：US06939626B2

公开(公告)日：2005-09-06

申请号：US10628011

申请日：2003-07-24

Applicant: Kai Tang

Inventor： Kai Tang

IPC: G11B5/00 ,  G11B5/012 ,  G11B5/09 ,  G11B5/64 ,  G11B5/65 ,  G11B5/66 ,  G11B5/738 ,  G11B5/74 ,  G11B5/851 ,  G11B5/673

CPC classification number: G11B5/66 ,  G11B5/012 ,  G11B5/09 ,  G11B5/656 ,  G11B5/74 ,  G11B5/851 ,  G11B2005/0002 ,  G11B2005/0005 ,  G11B2005/001 ,  Y10T428/1121 ,  Y10T428/1193 ,  Y10T428/24942 ,  Y10T428/24992

Abstract: Multiple embodiments of the invention are described which include at least two laminated ferromagnetic layers with differing magnetic anisotropy. The independent magnetic layer farther away from the recording head is selected to have a lower magnetic anisotropy to allow magnetic switching of the multiple magnetic layers to occur at approximately the same head write current even though the recording head field is reduced with increased distance from the head. The improved switching yields improved magnetic recording performance. Laminated magnetic media according to the invention can have a single peak in the normalized DC erase noise vs. head write current plot indicating that the magnetic transitions in the non-slave magnetic layers are written at the same head write current. As a result the magnetic pulse width (PW50) is reduced, overwrite (OW) is improved and media signal-to-noise ratio (SoNR) is improved. Alternatively one or both of the laminated ferromagnetic layers can be replaced with an antiferromagnetically (AF) coupled layer structure that has an AFC-master and an AFC-slave layer separated by a spacer layer selected to antiferromagnetically couple the AFC-master and AFC-slave layers.

Abstract translation: 描述了本发明的多个实施例，其包括具有不同磁各向异性的至少两个叠层铁磁层。 选择远离记录头的独立磁性层具有较低的磁各向异性，以允许多个磁性层的磁性切换以大致相同的磁头写入电流发生，即使记录磁头场随距离磁头的距离增加而减小 。 改进的开关产生改善的磁记录性能。 根据本发明的层压磁性介质可以在归一化的直流擦除噪声中相对于头写入电流图具有单峰，表明非从磁层中的磁转变以相同的磁头写入电流写入。 结果，减小了磁脉冲宽度（PW＆lt; 50＆gt;），改进了覆盖（OW），并提高了媒体信噪比（S SUB）。 或者，层叠的铁磁层中的一个或两个可以用反铁磁（AF）耦合层结构来代替，该结构具有由选择用于反铁磁耦合AFC主和AFC从站的间隔层分隔的AFC主站和AFC从站 层。

公开(公告)号：US06906879B1

公开(公告)日：2005-06-14

申请号：US10727703

申请日：2003-12-03

Applicant: Manfred Albrecht ,  Olav Hellwig ,  Guohan Hu ,  Bruce David Terris

Inventor： Manfred Albrecht ,  Olav Hellwig ,  Guohan Hu ,  Bruce David Terris

IPC: G11B5/64 ,  G11B5/00 ,  G11B5/012 ,  G11B5/02 ,  G11B5/09 ,  G11B5/127 ,  G11B5/31 ,  G11B5/65 ,  G11B5/66 ,  G11B5/667 ,  G11B5/673 ,  G11B5/738 ,  G11B5/82 ,  G11B5/855

CPC classification number: G11B5/66 ,  B82Y10/00 ,  G11B5/743 ,  G11B5/855 ,  G11B2005/0021

Abstract: A magnetic recording system, such as a magnetic recording disk drive, uses a patterned perpendicular magnetic recording medium where each magnetic block or island contains a stack of individual magnetic cells to provide multilevel recording. Each cell in an island is formed of a material or set of materials to provide the cell with perpendicular magnetic anisotropy and is a single magnetic domain. Each cell is magnetically decoupled from the other cells in its island by nonmagnetic spacer layers. Thus each cell can have a magnetization (magnetic moment) in one of two directions (into or out of the plane of the layer making up the cell), and this magnetization is independent of the magnetization of the other cells in its island, This permits multiple magnetic levels or states to be recorded in each magnetic island.

Abstract translation: 诸如磁记录盘驱动器的磁记录系统使用图案化的垂直磁记录介质，其中每个磁块或岛包含单个磁性单元的堆叠以提供多级记录。 岛中的每个单元由材料或材料组成，以向单元提供垂直的磁各向异性并且是单个磁畴。 每个单元通过非磁性间隔层与其岛中的其它单元磁耦合。 因此，每个电池可以在两个方向之一（进入或离开构成电池的层的平面）中具有磁化（磁矩），并且该磁化独立于其岛中的其他电池的磁化。这允许 要记录在每个磁岛中的多个磁级或状态。

公开(公告)号：US20050122612A1

公开(公告)日：2005-06-09

申请号：US10727703

申请日：2003-12-03

Applicant: Manfred Albrecht ,  Olav Hellwig ,  Guohan Hu ,  Bruce Terris

Inventor： Manfred Albrecht ,  Olav Hellwig ,  Guohan Hu ,  Bruce Terris

IPC: G11B5/64 ,  G11B5/00 ,  G11B5/012 ,  G11B5/02 ,  G11B5/09 ,  G11B5/127 ,  G11B5/31 ,  G11B5/65 ,  G11B5/66 ,  G11B5/667 ,  G11B5/673 ,  G11B5/738 ,  G11B5/82 ,  G11B5/855

CPC classification number: G11B5/66 ,  B82Y10/00 ,  G11B5/743 ,  G11B5/855 ,  G11B2005/0021

Abstract: A magnetic recording system, such as a magnetic recording disk drive, uses a patterned perpendicular magnetic recording medium where each magnetic block or island contains a stack of individual magnetic cells to provide multilevel recording. Each cell in an island is formed of a material or set of materials to provide the cell with perpendicular magnetic anisotropy and is a single magnetic domain. Each cell is magnetically decoupled from the other cells in its island by nonmagnetic spacer layers. Thus each cell can have a magnetization (magnetic moment) in one of two directions (into or out of the plane of the layer making up the cell), and this magnetization is independent of the magnetization of the other cells in its island. This permits multiple magnetic levels or states to be recorded in each magnetic island.

Abstract translation: 诸如磁记录盘驱动器的磁记录系统使用图案化的垂直磁记录介质，其中每个磁块或岛包含单个磁性单元的堆叠以提供多级记录。 岛中的每个单元由材料或材料组成，以向单元提供垂直的磁各向异性并且是单个磁畴。 每个单元通过非磁性间隔层与其岛中的其它单元磁耦合。 因此，每个单元可以在两个方向（组成单元的层的平面内或外）中的一个方向上具有磁化（磁矩），并且该磁化独立于其岛中的其它单元的磁化。 这允许在每个磁岛中记录多个磁级或状态。

公开(公告)号：US06893735B2

公开(公告)日：2005-05-17

申请号：US10444107

申请日：2003-05-22

Applicant: B. Ramamurthy Acharya ,  E. Noel Abarra

Inventor： B. Ramamurthy Acharya ,  E. Noel Abarra

IPC: G11B5/65 ,  G11B5/00 ,  G11B5/012 ,  G11B5/64 ,  G11B5/66 ,  G11B5/738 ,  G11B5/74 ,  G11B5/82 ,  G11B5/673

CPC classification number: G11B5/656 ,  G11B5/00 ,  G11B5/012 ,  G11B5/66 ,  G11B5/74 ,  G11B5/82 ,  G11B2005/0002 ,  G11B2005/0005 ,  Y10T428/12465 ,  Y10T428/12861 ,  Y10T428/12868 ,  Y10T428/12931

Abstract: A magnetic recording medium includes a nonmagnetic underlayer, an initial magnetic layer, a nonmagnetic spacer layer provided on the initial magnetic layer, and a final magnetic layer provided on the nonmagnetic spacer layer. The initial magnetic layer is disposed closer to the nonmagnetic underlayer than the final magnetic layer, and the initial and final magnetic layers are made of mutually different compositions and are anti-ferromagnetically coupled.

Abstract translation: 磁记录介质包括非磁性底层，初始磁性层，设置在初始磁性层上的非磁性间隔层，以及设置在非磁性间隔层上的最终磁性层。 初始磁性层被设置成比最终的磁性层更靠近非磁性底层，并且初始和最终的磁性层由相互不同的组成制成并且是反铁磁耦合的。

公开(公告)号：US20050042481A1

公开(公告)日：2005-02-24

申请号：US10959729

申请日：2004-10-06

Applicant: Kazumasa Shimoda ,  Takuya Uzumaki

Inventor： Kazumasa Shimoda ,  Takuya Uzumaki

IPC: G11B5/64 ,  G11B5/66 ,  G11B5/667 ,  G11B5/673 ,  G11B5/73 ,  G11B5/738 ,  G11B5/84 ,  G11B5/851

CPC classification number: G11B5/7325 ,  G11B5/656 ,  G11B5/66 ,  G11B5/8404 ,  Y10T428/265

Abstract: A perpendicular magnetic recording medium including a substrate, a roughness control layer provided on the substrate and having a rough surface with a grain size of 5 to 20 nm and an average roughness (Ra) of 0.2 to 2.0 nm, and an orientation control layer provided on the roughness control layer and containing 30 at % or more of metal solely having an fcc structure. The perpendicular magnetic recording medium further includes a magnetic recording layer having perpendicular magnetic anisotropy provided on the orientation control layer in contact therewith. The magnetic recording layer is formed from a multilayer film composed of ferromagnetic thin films and nonmagnetic thin films alternately stacked.

Abstract translation: 一种垂直磁记录介质，包括基板，设置在基板上的粗糙表面的平均粗糙度（Ra）为0.2〜2.0nm，平均粗糙度（Ra）为0.2〜2.0nm的粗糙面控制层，以及设置有取向控制层 在粗糙度控制层上，含有30原子％以上的仅具有fcc结构的金属。 垂直磁记录介质还包括具有与定向控制层接触的垂直磁各向异性的磁记录层。 磁记录层由交替堆叠的铁磁性薄膜和非磁性薄膜构成的多层膜形成。

公开(公告)号：US20050042367A1

公开(公告)日：2005-02-24

申请号：US10952735

申请日：2004-09-30

Applicant: Hiroaki Nemoto ,  Hiroyuki Nakagawa ,  Yuzuru Hosoe

Inventor： Hiroaki Nemoto ,  Hiroyuki Nakagawa ,  Yuzuru Hosoe

IPC: G11B5/00 ,  G11B5/64 ,  G11B5/66 ,  G11B5/673 ,  G11B5/738 ,  G11B5/84 ,  H01F10/16 ,  H01F41/32 ,  B05D3/00

CPC classification number: G11B5/84 ,  G11B5/656 ,  G11B5/66 ,  G11B2005/0029 ,  Y10T428/12646 ,  Y10T428/12875 ,  Y10T428/12931 ,  Y10T428/24975 ,  Y10T428/265

Abstract: A perpendicular magnetic recording medium, which has a low level of recording noise and sufficiently large perpendicular magnetic anisotropy energy relative to demagnetizing field energy, includes a substrate and a multi-layered magnetic film. The multi-layered magnetic film is composed of ferromagnetic metal layers of Co alloy containing at least Cr and non-magnetic metal layers of Pd alloy, each one layer of which are laminated alternately on top of one layer of the other. The ferromagnetic metal layers and the non-magnetic metal layers have a thickness of d1 and d2, respectively, with the ratio of d1/d2 being in the range of 1.5 to 4.0. This specific layer structure reduces the magnetic exchange interaction between magnetic particles in the multi-layered magnetic film. Therefore, the perpendicular magnetic recording medium is stable against thermal disturbance and has a low level of recording noise.

Abstract translation: 相对于去磁场能量，具有低水平的记录噪声和足够大的垂直磁各向异性能的垂直磁记录介质包括基底和多层磁性膜。 多层磁性膜由至少含有Cr的Co合金的铁磁性金属层和Pd合金的非磁性金属层构成，其中的每一层交替层叠在另一层之上。 强磁性金属层和非磁性金属层的厚度分别为d1和d2，d1 / d2的比例在1.5至4.0的范围内。 该特定的层结构减少了多层磁性膜中磁性颗粒之间的磁交换相互作用。 因此，垂直磁记录介质对于热干扰是稳定的并且具有低水平的记录噪声。

公开(公告)号：US06846581B2

公开(公告)日：2005-01-25

申请号：US10101949

申请日：2002-03-21

Applicant: Soichi Oikawa ,  Yoichiro Tanaka ,  Takashi Hikosaka ,  Futoshi Nakamura

Inventor： Soichi Oikawa ,  Yoichiro Tanaka ,  Takashi Hikosaka ,  Futoshi Nakamura

IPC: G11B5/64 ,  G11B5/65 ,  G11B5/66 ,  G11B5/667 ,  G11B5/673 ,  G11B5/738 ,  H01F10/16 ,  H01F10/30 ,  B32B19/00

CPC classification number: G11B5/66

Abstract: Disclosed is a perpendicular magnetic recording medium, comprising a nonmagnetic substrate, a longitudinal hard magnetic multi-layered film arranged on the nonmagnetic substrate, including a nonmagnetic intermediate layer and a pair of hard magnetic layers laminated one upon the other with the nonmagnetic intermediate layer interposed therebetween, and having at least two hard magnetic layers, a longitudinal soft magnetic layer formed on the longitudinal hard magnetic multi-layered film, and a perpendicular magnetic recording layer formed on the longitudinal soft magnetic layer. The perpendicular magnetic recording medium of the particular construction is capable of suppressing noise and achieves a high recording magnetic field intensity and a high recording resolution.

Abstract translation: 公开了一种垂直磁记录介质，包括非磁性基板，布置在非磁性基板上的纵向硬磁性多层膜，包括非磁性中间层和一对彼此层叠的硬磁性层，其中非磁性中间层插入 并且具有至少两个硬磁性层，形成在纵向硬磁性多层膜上的纵向软磁性层和形成在纵向软磁性层上的垂直磁记录层。 具体结构的垂直磁记录介质能够抑制噪声，并且实现高记录磁场强度和高记录分辨率。

公开(公告)号：US4678721A

公开(公告)日：1987-07-07

申请号：US869483

申请日：1986-06-02

Applicant: Friedrich J. A. den Broeder ,  Henricus J. G. Draaisma ,  Alexander Kahle

Inventor： Friedrich J. A. den Broeder ,  Henricus J. G. Draaisma ,  Alexander Kahle

IPC: G11B5/64 ,  G11B5/65 ,  G11B5/66 ,  G11B5/673 ,  G11B5/85 ,  B21C37/00

CPC classification number: G11B5/66 ,  Y10S428/928 ,  Y10T428/12438 ,  Y10T428/12465 ,  Y10T428/12569 ,  Y10T428/12597 ,  Y10T428/12632 ,  Y10T428/12674 ,  Y10T428/12861 ,  Y10T428/12875

Abstract: The invention provides a magnetic recording medium comprising a substrate of a nonmagnetic material bearing a thin magnetic layer with perpendicular anistropy. The magnetic thin layer comprises alternate layers of Pd and Co. The signal-to-noise ratio upon reading the stored information is considerably improved in that the thicknesses of the individual layers of Pd are between 0.2 and 2.0 nm and that the individual layers of Co consist of at least one monolayer of Co atoms and have thicknesses which are smaller than 0.3 nm.The thin magnet layer may be manufactured, for example, by electron beam vacuum vapor deposition of the individual layers of Pd and Co.

公开(公告)号：US09607645B2

公开(公告)日：2017-03-28

申请号：US14642251

申请日：2015-03-09

Applicant: Kabushiki Kaisha Toshiba

Inventor： Hideaki Fukuzawa ,  Hiromi Yuasa

IPC: G11B5/012 ,  G11B5/127 ,  G11B7/0037 ,  G11B5/66 ,  G11B5/673 ,  G11B5/02 ,  G11B5/39 ,  B82Y10/00 ,  G11B5/31 ,  G11B5/74 ,  G11B5/82 ,  G11B5/00

CPC classification number: G11B5/66 ,  B82Y10/00 ,  G11B5/02 ,  G11B5/314 ,  G11B5/3983 ,  G11B5/743 ,  G11B5/746 ,  G11B5/82 ,  G11B2005/0002 ,  G11B2005/0024

Abstract: A magnetic recording device includes: a magnetic recording medium containing a plurality of recording layers; a magnetic recording head for conducting magnetic writing of information in the magnetic recording medium; and a magnetic reproducing head for conducting magnetic reading out of the information from the magnetic recording medium; wherein the magnetic recording head includes a high frequency oscillator for magnetically assisting the magnetic writing of the information so as to change a magnetization of at least one of the plurality of recording layers of the magnetic recording medium, thereby recording a plurality of information different from one another in the magnetic recording medium commensurate with a total amount of magnetization of the plurality of recording layers.

公开(公告)号：US09028985B2

公开(公告)日：2015-05-12

申请号：US13077419

申请日：2011-03-31

Applicant: Mrugesh Desai ,  Kyongha Kang ,  Jian Zhou ,  B. Ramamurthy Acharya

Inventor： Mrugesh Desai ,  Kyongha Kang ,  Jian Zhou ,  B. Ramamurthy Acharya

IPC: G11B5/673 ,  G11B5/66 ,  G11B5/65

CPC classification number: G11B5/66 ,  G11B5/65

Abstract: A magnetic recording (PMR) disk structure is described. The PMR disk structure may include a magnetic capping layer being substantially free of an oxide, an upper magnetic layer with an oxide content disposed directly below and in contact with the magnetic capping layer, and an upper exchange coupling layer disposed below the upper magnetic layer.

Abstract translation: 描述磁记录（PMR）盘结构。 PMR盘结构可以包括基本上不含氧化物的磁性覆盖层，具有氧化物含量的上部磁性层直接设置在磁性覆盖层的下方并与之接触，以及设置在上部磁性层下方的上部交换耦合层。