公开(公告)号：US20230059734A1

公开(公告)日：2023-02-23

申请号：US17587499

申请日：2022-01-28

Applicant: SHOWA DENKO K.K.

Inventor： Sho TONEGAWA ,  Akira SAKAWAKI ,  Daizo ENDO ,  Kota HASEGAWA

IPC: H03H9/17 ,  H01L41/047 ,  H03H9/02

Abstract: A piezoelectric film including a piezoelectric body configured to extract radio waves of a required frequency by resonance is provided. The piezoelectric body is based on either of ScAlN or AlN, and an X-ray rocking curve full-width at half-maximum (FWHM) of the piezoelectric body in a lattice plane with a Miller index of (11-20) is not more than 10°.

公开(公告)号：US20160148633A1

公开(公告)日：2016-05-26

申请号：US14935529

申请日：2015-11-09

Applicant: SHOWA DENKO K.K. ,  JAPAN ATOMIC ENERGY AGENCY

Inventor： Kota HASEGAWA ,  Takahiro UKAI ,  Eishin YAMAKAWA ,  Shiro ENTANI ,  Seiji SAKAI

IPC: G11B5/73 ,  G11B5/72 ,  G11B5/127

CPC classification number: G11B5/72 ,  G11B5/66 ,  G11B5/82

Abstract: A perpendicular magnetic recording medium includes a perpendicular magnetic layer provided above a nonmagnetic substrate, and a protection layer provided on the perpendicular magnetic layer. The perpendicular magnetic layer has an hcp structure, and includes stacked layers having a (0002) crystal plane oriented parallel to a surface of the nonmagnetic substrate. An uppermost layer amongst the stacked layers includes polycrystal grains selected from a CoCr-base alloy, a CoPt-base alloy, a CoCrPt-base alloy, and a CoPtCr-base alloy. The protection layer makes contact with the uppermost layer of the perpendicular magnetic layer, and includes a single graphene layer or a graphene stack, and an amorphous carbon layer. The single graphene layer or the graphene stack is bonded in parallel to a (0002) crystal plane of the polycrystal grains.

Abstract translation: 垂直磁记录介质包括设置在非磁性衬底上的垂直磁性层和设置在垂直磁性层上的保护层。 垂直磁性层具有hcp结构，并且包括具有平行于非磁性基底的表面取向的（0002）晶面的堆叠层。 堆叠层中的最上层包括选自CoCr基合金，CoPt基合金，CoCrPt基合金和CoPtCr基合金的多晶粒。 保护层与垂直磁性层的最上层接触，并且包括单个石墨烯层或石墨烯叠层和无定形碳层。 单个石墨烯层或石墨烯层与多晶粒的（0002）晶面平行地结合。

公开(公告)号：US20190295583A1

公开(公告)日：2019-09-26

申请号：US16279143

申请日：2019-02-19

Applicant: SHOWA DENKO K.K.

Inventor： Kota HASEGAWA ,  Katsuaki TO

IPC: G11B5/667 ,  G11B5/706 ,  C23C16/505 ,  C23C16/28 ,  C22C19/07

Abstract: A magnetic recording medium includes a nonmagnetic substrate, a soft magnetic underlayer, an orientation control layer, a perpendicular magnetic layer, and a protection layer that are arranged in this order. The perpendicular magnetic layer includes a first magnetic layer and a second magnetic layer that are arranged in this order on the orientation control layer. The first magnetic layer has a granular structure including an oxide at grain boundary parts of magnetic grains, and the second magnetic layer is closest to the protection layer among layers within the perpendicular magnetic layer, and includes magnetic grains made of a CoCrPt alloy, and a nitride of carbon or a hydride of carbon.

公开(公告)号：US20170221515A1

公开(公告)日：2017-08-03

申请号：US15361658

申请日：2016-11-28

Applicant: SHOWA DENKO K.K.

Inventor： Ken INOUE ,  Kota HASEGAWA

IPC: G11B5/66

CPC classification number: G11B5/66

Abstract: A magnetic recording medium includes a non-magnetic substrate on which at least a soft magnetic underlayer, an orientation control layer, a perpendicular magnetic layer, and a protective layer are disposed. The perpendicular magnetic layer includes first to fourth magnetic layers. A first exchange coupling control layer is disposed between the first magnetic layer and the second magnetic layer. A second exchange coupling control layer is disposed between the second magnetic layer and the third magnetic layer. Following relations are satisfied where Kui is a magnetic anisotropic constant of an i-th magnetic layer, Msi is a saturation magnetization of the i-th magnetic layer, and t1 is a film thickness of the i-th magnetic layer, Ku1>Ku2, Ku2>Ku3, Ms1×t1>Ms2×t2, Ms2×t2>Ms3×t3 r Ku3

公开(公告)号：US20210366510A1

公开(公告)日：2021-11-25

申请号：US17325347

申请日：2021-05-20

Applicant: SHOWA DENKO K.K.

Inventor： Kota HASEGAWA ,  Takayuki FUKUSHIMA

IPC: G11B5/02 ,  G11B5/73

Abstract: A magnetic recording medium includes a substrate, an underlayer disposed above the substrate, and a first magnetic layer disposed above the underlayer. The first magnetic layer has a granular structure including magnetic grains having a L10 structure, and grain boundaries. A content of the grain boundaries is in a range of 25 volume percent to 50 volume percent, and the grain boundaries include a chalcogenide-based layered material.

公开(公告)号：US20210005219A1

公开(公告)日：2021-01-07

申请号：US16907676

申请日：2020-06-22

Applicant: SHOWA DENKO K.K.

Inventor： Kota HASEGAWA ,  Yu AZUMA

IPC: G11B5/73 ,  G11B5/851 ,  G11B5/667

Abstract: A magnetic recording medium includes a non-magnetic substrate; a soft magnetic layer; a first seed layer; a second seed layer; an underlayer; and a perpendicular magnetic recording layer. The soft magnetic layer, the first seed layer, the second seed layer, the underlayer and the perpendicular magnetic recording layer are disposed on the non-magnetic substrate in this order. The first seed layer includes MoS2, hexagonal-BN, WS2, WSe2 or graphite. The second seed layer includes AlN having a hexagonal wurtzite type crystal structure. The underlayer includes Ru.

公开(公告)号：US20210098017A1

公开(公告)日：2021-04-01

申请号：US16953894

申请日：2020-11-20

Applicant: SHOWA DENKO K.K.

Inventor： Kota HASEGAWA ,  Katsuaki TO

IPC: G11B5/667 ,  G11B5/706 ,  C23C16/28 ,  C22C19/07 ,  C23C16/505 ,  G11B5/65 ,  G11B5/66

Abstract: A magnetic recording medium includes a nonmagnetic substrate, a soft magnetic underlayer, an orientation control layer, a perpendicular magnetic layer, and a protection layer that are arranged in this order. The perpendicular magnetic layer includes a first magnetic layer and a second magnetic layer that are arranged in this order on the orientation control layer. The first magnetic layer has a granular structure including an oxide at grain boundary parts of magnetic grains, and the second magnetic layer is closest to the protection layer among layers within the perpendicular magnetic layer, and includes magnetic grains made of a CoCrPt alloy, and a nitride of carbon or a hydride of carbon.

公开(公告)号：US20180174605A1

公开(公告)日：2018-06-21

申请号：US15844717

申请日：2017-12-18

Applicant: SHOWA DENKO K.K.

Inventor： Kota HASEGAWA ,  Haruhisa OHASHI

IPC: G11B5/667 ,  C23C14/00 ,  C23C28/00 ,  G11B5/65 ,  G11B5/73 ,  G11B5/851 ,  G11B5/82 ,  C23C14/35

Abstract: A magnetic recording medium includes a non-magnetic substrate, a soft magnetic underlayer, an orientation control layer, a perpendicular magnetic layer, and a protective layer arranged in this order. The perpendicular magnetic layer includes a first magnetic layer and a second magnetic layer from the non-magnetic substrate side in this order. The second magnetic layer contains a magnetic grain and provided farthest from the non-magnetic substrate. The first magnetic layer has a granular structure that contains an oxide in a grain boundary. The second magnetic layer has a granular structure that contains a carbide of an element contained in the magnetic grain in a grain boundary.

公开(公告)号：US20180166100A1

公开(公告)日：2018-06-14

申请号：US15831579

申请日：2017-12-05

Applicant: SHOWA DENKO K.K.

Inventor： Kota HASEGAWA ,  Haruhisa OHASHI

IPC: G11B5/667 ,  G11B5/65 ,  G11B5/851 ,  G11B5/73

Abstract: A magnetic recording medium includes a non-magnetic substrate, a soft magnetic underlayer, an orientation control layer, a perpendicular magnetic layer, and a protective layer arranged in this order. The perpendicular magnetic layer includes a first magnetic layer and a second magnetic layer from the non-magnetic substrate side in this order. The second magnetic layer contains a magnetic grain and provided farthest from the non-magnetic substrate. The first magnetic layer has a granular structure that contains an oxide in a grain boundary. The second magnetic layer has a granular structure that contains a nitride of an element contained in the magnetic grain in a grain boundary.