公开(公告)号：US11024334B2

公开(公告)日：2021-06-01

申请号：US16835770

申请日：2020-03-31

Applicant: SHOWA DENKO K.K.

Inventor： Takayuki Fukushima ,  Chen Xu ,  Lei Zhang ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Kazuya Niwa ,  Tomoo Shige ,  Hiroaki Nemoto ,  Yuji Umemoto ,  Hiroshi Koyanagi

IPC: G11B11/105 ,  G11B5/65 ,  G11B5/66 ,  G11B5/60 ,  G11B5/00

Abstract: A magnetic recording medium includes a substrate, an underlayer, and a magnetic layer that are arranged in this order. The magnetic layer has a granular structure including magnetic grains having a L10 crystal structure, and grain boundary parts having a volume fraction in a range of 25 volume % to 50 volume %. The magnetic grains have a c-axis orientation with respect to the substrate. The grain boundary parts include a material having a lattice constant in a range of 0.30 nm to 0.36 nm, or in a range of 0.60 nm to 0.72 nm.

公开(公告)号：US10283154B2

公开(公告)日：2019-05-07

申请号：US15979965

申请日：2018-05-15

Applicant: SHOWA DENKO K.K. ,  TOHOKU UNIVERSITY

Inventor： Shintaro Hinata ,  Shin Saito ,  Takayuki Fukushima ,  Haruhisa Ohashi ,  Kazuya Niwa ,  Lei Zhang ,  Yuji Murakami ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Tetsuya Kanbe ,  Tomoo Shige

IPC: G11B5/65 ,  G11B5/66 ,  G11B5/48 ,  G11B5/73 ,  G11B5/00 ,  G11B5/60

Abstract: A magnetic recording medium includes a substrate, a barrier layer, a crystal grain size control layer, and a magnetic layer that are arranged in this order. The barrier layer includes at least one of oxides, nitrides, and carbides, and the crystal grain size control layer is a crystalline layer including Ag and having an average thickness in a range of 0.1 nm to 1 nm. The barrier layer makes contact with the crystal grain size control layer, and the magnetic layer includes an alloy having a L10 crystal structure and a (001) face orientation.

公开(公告)号：US09230588B2

公开(公告)日：2016-01-05

申请号：US14326555

申请日：2014-07-09

Applicant: SHOWA DENKO K.K.

Inventor： Lei Zhang ,  Tetsuya Kanbe ,  Yuji Murakami ,  Kazuya Niwa

IPC: G11B5/73 ,  G11B5/65 ,  G11B5/00

CPC classification number: G11B5/65 ,  G11B5/7325 ,  G11B2005/0021

Abstract: A magnetic recording medium includes a substrate, a magnetic layer including an alloy having an L10 type crystal structure as a main component thereof, a plurality of underlayers arranged between the substrate and the magnetic layer, and a barrier layer made of a material having an NaCl structure. The plurality of underlayers include at least one crystalline underlayer including Mo as a main component thereof, and at least one of Si and C in a range of 1 mol % to 20 mol % and an oxide in a range of 1 vol % to 50 vol %. The barrier layer is provided between the magnetic layer and the at least one crystalline underlayer including Mo.

Abstract translation: 磁记录介质包括基板，包括具有L10型晶体结构的合金作为其主要成分的磁性层，布置在基板和磁性层之间的多个底层，以及由具有NaCl的材料制成的阻挡层 结构体。 多个底层包括至少一种包含Mo作为其主要成分的晶体底层，以及Si和C中的至少一种在1mol％至20mol％的范围内，氧化物在1vol％至50vol ％。 阻挡层设置在磁性层和包含Mo的至少一个结晶底层之间。

公开(公告)号：US08792313B2

公开(公告)日：2014-07-29

申请号：US13972041

申请日：2013-08-21

Applicant: Showa Denko K.K.

Inventor： Kazuya Niwa ,  Tetsuya Kanbe ,  Yuji Murakami ,  Lei Zhang

IPC: G11B11/00

CPC classification number: G11B13/08 ,  G11B5/65 ,  G11B5/73 ,  G11B5/7325 ,  G11B2005/0024

Abstract: A magnetic recording medium of the present invention includes an under layer formed on a substrate, and a magnetic layer, formed on the under layer, which contains an alloy having an L10-type crystal structure as a main component. The under layer includes, in order from the substrate side, a first under layer with a lattice constant a of 2.87 Å≦a

Abstract translation: 本发明的磁记录介质包括形成在基板上的底层和形成在下层上的磁性层，其含有具有L10型晶体结构的合金作为主要成分。 底层从衬底侧依次包括具有晶格常数a为2.87的第一底层; a <3.04，具有晶格常数a为3.04和nlE的BCC结构的第二下层; a <3.18 Å，具有晶格常数a为3.18和n1E;a≤331的BCC结构的第三下层，以及具有NaCl型晶体结构的上下层。 第一底层具有B2结构，或具有含有Cr作为主要成分的BCC结构。 在本发明的磁记录介质中，使用热辅助磁记录型或微波辅助磁记录型来记录信息。

公开(公告)号：US11823721B2

公开(公告)日：2023-11-21

申请号：US17649588

申请日：2022-02-01

Applicant: SHOWA DENKO K.K.

Inventor： Yoshitaka Aono ,  Takahiro Ukai ,  Takanao Ebisawa ,  Kazuya Niwa ,  Takayuki Konno

IPC: G11B5/667 ,  G11B5/66 ,  G11B5/851

CPC classification number: G11B5/667 ,  G11B5/672 ,  G11B5/851

Abstract: A magnetic recording medium including: a non-magnetic substrate; an underlayer; a perpendicular magnetic layer; a diffusion preventing layer; and a protective layer, wherein the underlayer, the perpendicular magnetic layer, the diffusion preventing layer, and the protective layer are layered on the non-magnetic substrate in this order, the perpendicular magnetic layer has a multi-layer structure, the perpendicular magnetic layer includes an uppermost layer and at least one layer other than the uppermost layer, the uppermost layer including Co or Fe in magnetic particles, and the at least one layer other than the uppermost layer including an oxide, the diffusion preventing layer is provided between the perpendicular magnetic layer and the protective layer, and the diffusion preventing layer includes at least one component selected from a group consisting of Si, Ti, Cr, B, and Ru, or either a carbide, an oxide, or both, of the at least one component.

公开(公告)号：US11244700B2

公开(公告)日：2022-02-08

申请号：US16169065

申请日：2018-10-24

Applicant: SHOWA DENKO K.K.

Inventor： Katsumi Murofushi ,  Yoshitaka Ishibashi ,  Takayuki Fukushima ,  Kazuya Niwa ,  Lei Zhang ,  Yuji Murakami ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Chen Xu ,  Tetsuya Kanbe ,  Tomoo Shige

IPC: G11B5/65 ,  G11B5/72 ,  G11B5/82 ,  G11B5/851 ,  C08L61/28

Abstract: A magnetic recording medium includes a substrate, an underlayer provided on the substrate, and a magnetic layer provided on the underlayer and having a L10 structure and a (001) orientation. The magnetic layer has a granular structure in which an organic compound having a methylene skeleton or a methine skeleton is arranged at grain boundaries of magnetic grains.

公开(公告)号：US09245567B2

公开(公告)日：2016-01-26

申请号：US14305118

申请日：2014-06-16

Applicant: SHOWA DENKO K.K.

Inventor： Tetsuya Kanbe ,  Kazuya Niwa ,  Yuji Murakami ,  Lei Zhang

IPC: G11B5/66 ,  G11B5/738 ,  G11B5/65 ,  G11B5/73

CPC classification number: G11B5/738 ,  G11B5/65 ,  G11B5/66 ,  G11B5/7325

Abstract: A magnetic recording medium includes a substrate, a magnetic layer including a FePt alloy having a L10 type structure, and a plurality of underlayers arranged between the substrate and the magnetic layer, wherein at least one of the plurality of underlayers includes TiO2.

Abstract translation: 磁记录介质包括基板，包括具有L10型结构的FePt合金的磁性层和布置在基板和磁性层之间的多个底层，其中多个底层中的至少一个包括TiO 2。

公开(公告)号：US11037591B2

公开(公告)日：2021-06-15

申请号：US16433377

申请日：2019-06-06

Applicant: SHOWA DENKO K.K.

Inventor： Lei Zhang ,  Chen Xu ,  Takayuki Fukushima ,  Kazuya Niwa ,  Tetsuya Kanbe ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Tomoo Shige

IPC: G11B5/73 ,  G11B5/65 ,  G11B5/00

Abstract: A heat-assisted magnetic recording medium includes: a substrate; an underlayer; and a magnetic layer including an alloy having an L10 structure, wherein the underlayer includes, from the substrate side, a bcc underlayer including a substance having a bcc structure, a first oxide layer that is in contact with the bcc underlayer, and a second oxide layer that is in contact with the magnetic layer. The bcc underlayer, the first oxide layer, and the second oxide layer are stacked in the recited order. The first oxide layer and the second oxide layer include magnesium oxide, and the second oxide layer further includes one or more compounds selected from the group consisting of vanadium oxide, vanadium nitride, and vanadium carbide.

公开(公告)号：US10008220B2

公开(公告)日：2018-06-26

申请号：US15596109

申请日：2017-05-16

Applicant: SHOWA DENKO K.K.

Inventor： Takayuki Fukushima ,  Yuji Murakami ,  Tetsuya Kanbe ,  Lei Zhang ,  Kazuya Niwa ,  Hisato Shibata

IPC: G11B5/82 ,  G11B5/187 ,  G11B5/706 ,  G11B5/74 ,  G11B5/716 ,  G11B5/855 ,  G11B5/39 ,  G11B5/66 ,  G11B5/73 ,  G11B5/84 ,  G11B5/65

CPC classification number: G11B5/1875 ,  G11B5/398 ,  G11B5/65 ,  G11B5/66 ,  G11B5/706 ,  G11B5/70615 ,  G11B5/716 ,  G11B5/73 ,  G11B5/743 ,  G11B5/82 ,  G11B5/8404 ,  G11B5/855

Abstract: A magnetic recording medium includes a substrate; a lower base layer formed on the substrate; and a (001) oriented L10 magnetic layer formed on the lower base layer and including a first magnetic layer formed on the lower base layer and having a granular structure of magnetic grains and a grain boundary portion, the grain boundary portion containing C, and a second magnetic layer formed on the first magnetic layer and having a granular structure of magnetic grains and a grain boundary portion, the grain boundary portion containing oxide or nitride, the second magnetic layer further containing one or more elements selected from a group consisting of Mg, Ni, Zn, Ge, Pd, Sn, Ag, Re, Au and Pb as an additive.

公开(公告)号：US20150085628A1

公开(公告)日：2015-03-26

申请号：US14394958

申请日：2013-05-10

Applicant: SHOWA DENKO K.K.

Inventor： Kazuya Niwa ,  Tetsuya Kanbe ,  Yuji Murakami ,  Lei Zhang

IPC: G11B5/73 ,  G11B5/65

CPC classification number: G11B5/7325 ,  G11B5/65 ,  G11B5/653 ,  G11B5/656 ,  G11B5/66 ,  G11B11/10589 ,  G11B2005/0021 ,  G11B2005/0024

Abstract: A thermally-assisted magnetic recording medium or a microwave-assisted magnetic recording medium includes: an orientation control layer (104) that is formed on a substrate (101); an underlayer (10) that is formed on the orientation control layer (104); and a magnetic layer (108) that is formed on the underlayer (10) and contains an alloy having an L10 type crystal structure as a main component, in which the underlayer (10) includes an MgO underlayer (107) that contains MgO and has a (100) orientation and a nitride underlayer (106) that contains at least one nitride selected from the group consisting of TaN, NbN, and HfN and has a (100) orientation.

Abstract translation: 热辅助磁记录介质或微波辅助磁记录介质包括：形成在基板（101）上的取向控制层（104）; 形成在取向控制层（104）上的底层（10）; 以及形成在所述下层（10）上并含有具有L10型晶体结构的合金作为主要成分的磁性层（108），其中所述底层（10）包括含有MgO的MgO底层（107），并且具有 （100）取向和含有选自TaN，NbN和HfN中的至少一种氮化物并具有（100）取向的氮化物底层（106）。