公开(公告)号：US20040197607A1

公开(公告)日：2004-10-07

申请号：US10833001

申请日：2004-04-28

Applicant: Hitachi, Ltd.

Inventor： Kiwamu Tanahashi ,  Atsushi Kikugawa ,  Yukio Honda ,  Masaaki Futamoto ,  Akira Ishikawa

IPC: G11B005/66

CPC classification number: B82Y25/00 ,  B82Y10/00 ,  G11B5/00 ,  G11B5/3909 ,  G11B5/653 ,  G11B5/667 ,  G11B5/7325 ,  G11B2005/0029

Abstract: A double layer perpendicular magnetic recording medium having a high medium S/N ratio at a recording density of 50 Gb/in2 or higher and a magnetic storage apparatus with a lower error rate and excellent reliability are provided. In a perpendicular magnetic recording medium in which a soft magnetic underlayer 12, an intermediate layer 13, and a perpendicular magnetic recording layer 14 are sequentially formed on a substrate 11, the intermediate layer 13 is made to be a non-magnetic amorphous alloy, in which Ni is a main component and Zr is contained, and the soft magnetic underlayer 12 is constituted of ferromagnetic nan-crystals precipitated by annealing.

Abstract translation: 提供了一种记录密度为50Gb / in 2或更高的具有高介质S / N比的双层垂直磁记录介质和具有较低误码率和优异可靠性的磁存储装置。 在其中在基板11上依次形成软磁性底层12，中间层13和垂直磁记录层14的垂直磁记录介质中，使中间层13成为非磁性非晶合金， 该Ni是主成分，含有Zr，软磁性底层12由通过退火而析出的铁磁性纳米晶体构成。

公开(公告)号：US20020018920A1

公开(公告)日：2002-02-14

申请号：US09862452

申请日：2001-05-23

Applicant: Hitachi, Ltd.

Inventor： Tomoo Yamamoto ,  Ichiro Tamai ,  Kiwamu Tanahashi ,  Akira Ishikawa

IPC: G11B005/73

CPC classification number: G11B5/7325 ,  G11B5/00 ,  G11B5/656 ,  G11B5/7379 ,  G11B2005/001

Abstract: A magnetic recording apparatus of a large capacity capable of super-high density recording of 10 Gbits or more per one square inch has a magnetic recording medium prepared by forming a Co alloy magnetic layer by way of an underlayer comprising Co or Cr alloy on a substrate, in which an amorphous or micro crystal seed layer containing at least Ti and Al is disposed between the substrate and the underlayer, the magnetic layer has an h.c.p. structure and is grown to (1.1.0) direction parallel with the substrate, the magnetic recording medium of high coercivity and reduced noises and undergoing less effects of thermal fluctuation being provided because of in-plane orientation of the axis of easy magnetization of the magnetic layer and the reduced size of the magnetic crystal grains and dispersion thereof, combination of the magnetic recording medium and the magnetic head having a read only device utilizing the magnetoresistive effect capable of providing a magnetic recording apparatus having a recording density at 10 Gbits or more per one square inch.

Abstract translation: 具有能够每平方英寸高10Gb或更高的超高密度记录的大容量的磁记录装置具有磁记录介质，该磁记录介质是通过在衬底上形成包含Co或Cr合金的底层的Co合金磁性层而制备的 其中至少含有Ti和Al的非晶或微晶晶种子层设置在基底和底层之间，磁性层具有hcp 结构，并且与基板平行生长（1.1.0）方向，由于磁性容易磁化的轴的面内定向，因此提供了高矫顽力和降低的噪声并且发生较少的热波动效应的磁记录介质 磁性晶粒和其分散体的尺寸减小，磁记录介质和具有只读器件的磁头的组合利用磁阻效应，能够提供具有10Gb或更高记录密度的磁记录装置 一平方英寸

公开(公告)号：US20020058161A1

公开(公告)日：2002-05-16

申请号：US09941735

申请日：2001-08-30

Applicant: Hitachi, Ltd.

Inventor： Tomoo Yamamoto ,  Ichiro Tamai ,  Akira Ishikawa

IPC: G11B005/66

CPC classification number: G11B5/667 ,  G11B5/66 ,  G11B5/7325 ,  Y10S428/90 ,  Y10T428/12465 ,  Y10T428/265

Abstract: A large-capacity magnetic storage apparatus is disclosed, capable of performing ultra-high density magnetic recording of 50 gigabits or more per 1 square inch. In a perpendicular magnetic recording medium having a non-magnetic intermediate layer and a magnetic recording layer sequentially formed, the non-magnetic intermediate layer is composed of a layer having a face-centered cubic structure and containing a non-magnetic elements excluding Pt. Specifically, the intermediate layer mainly contains at least one selected from the group of elements constituted of Al, Cu, Rh, Pd, Ag, Ir and Au, and is composed of a film having a face-centered cubic (f. c. c.) structure. The magnetic recording layer contains at least Co, Cr and Pt, and is composed of a film having a hexagonal close-packed (h. c. p.) structure. More preferably, a non-magnetic h. c. p. intermediate layer is provided between the non-magnetic intermediate layer and the magnetic recording layer.

Abstract translation: 公开了一种能够进行每1平方英寸50吉比特或更高的超高密度磁记录的大容量磁存储装置。 在具有顺序地形成非磁性中间层和磁记录层的垂直磁记录介质中，非磁性中间层由具有面心立方结构并包含除Pt以外的非磁性元素的层组成。 具体地说，中间层主要含有选自由Al，Cu，Rh，Pd，Ag，Ir和Au构成的元素组中的至少一种，并且由具有面心立方（c。c。）结构的膜组成。 磁记录层至少含有Co，Cr和Pt，并且由具有六方密堆积（h.p.P。）结构的膜组成。 更优选地，非磁性h。 C。 p。 中间层设置在非磁性中间层和磁记录层之间。

公开(公告)号：US20040043258A1

公开(公告)日：2004-03-04

申请号：US10650809

申请日：2003-08-29

Applicant: Hitachi, Ltd.

Inventor： Tomoo Yamamoto ,  Ichiro Tamai ,  Akira Ishikawa

IPC: H01F001/00

CPC classification number: G11B5/667 ,  G11B5/66 ,  G11B5/7325 ,  Y10S428/90 ,  Y10T428/12465 ,  Y10T428/265

Abstract: A large-capacity magnetic storage apparatus is disclosed, capable of performing ultra-high density magnetic recording of 50 gigabits or more per 1 square inch. In a perpendicular magnetic recording medium having a non-magnetic intermediate layer and a magnetic recording layer sequentially formed, the non-magnetic intermediate layer is composed of a layer having a face-centered cubic structure and containing a non-magnetic elements excluding Pt. Specifically, the intermediate layer mainly contains at least one selected from the group of elements constituted of Al, Cu, Rh, Pd, Ag, Ir and Au, and is composed of a film having a face-centered cubic (f. c. c.) structure. The magnetic recording layer contains at least Co, Cr and Pt, and is composed of a film having a hexagonal close-packed (h. c. p.) structure. More preferably, a non-magnetic h. c. p. intermediate layer is provided between the non-magnetic intermediate layer and the magnetic recording layer.

Abstract translation: 公开了一种能够进行每1平方英寸50吉比特或更高的超高密度磁记录的大容量磁存储装置。 在具有顺序地形成非磁性中间层和磁记录层的垂直磁记录介质中，非磁性中间层由具有面心立方结构并包含除Pt以外的非磁性元素的层组成。 具体地说，中间层主要含有选自由Al，Cu，Rh，Pd，Ag，Ir和Au构成的元素组中的至少一种，并且由具有面心立方（c。c。）结构的膜组成。 磁记录层至少含有Co，Cr和Pt，并且由具有六方密堆积（h.p.P。）结构的膜组成。 更优选地，非磁性h。 C。 p。 中间层设置在非磁性中间层和磁记录层之间。

公开(公告)号：US20020168547A1

公开(公告)日：2002-11-14

申请号：US10137398

申请日：2002-05-03

Applicant: Hitachi, Ltd.

Inventor： Tetsuya Kanbe ,  Yoshio Takahashi ,  Akira Ishikawa ,  Ichiro Tamai ,  Yuzuru Hosoe ,  Yoshifumi Matsuda ,  Kiwamu Tanahashi ,  Tomoo Yamamoto

IPC: G11B005/65

CPC classification number: G11B5/65 ,  G11B5/64 ,  G11B5/653 ,  Y10S428/90 ,  Y10T428/12465 ,  Y10T428/12854 ,  Y10T428/26 ,  Y10T428/265

Abstract: The present invention provides a magnetic recording medium having a magnetic layer deposited on a substrate through a single-layer underlayer or a multilayer-underlayer, the magnetic layer includes magnetic crystal grains having an acicular structure or amorphous magnetic particles, an average grain size of the magnetic grain and a grain-size dispersion normalized by the average grain size are less than 16 nm and less than 0.5, respectively, a value Kunullv/kT which results from dividing a product of a magnetic anisotropy constant Ku and a volume v of the magnetic grain by a product of a Boltzmann constant k and an absolute temperature T is selected to be greater than 60, and a film thickness of the magnetic layer falls within twice of the average grain size. Thus, there can be realized a magnetic recording system in which a media noise can be reduced, a high S/N and a low bit error rate can be obtained and which has a high recording density of 2 gigabits per one square inches and an MTBF (mean time between failure) of higher than 300000 hours.

Abstract translation: 本发明提供一种具有通过单层底层或多层下层沉积在基板上的磁性层的磁记录介质，该磁性层包括具有针状结构或无定形磁性颗粒的磁性晶粒，平均粒径为 磁性晶粒和由平均晶粒尺寸归一化的晶粒尺寸分散度分别小于16nm且小于0.5，由将磁各向异性常数Ku与体积v的积分开而产生的Ku.v / kT值 通过玻耳兹曼常数k和绝对温度T的乘积的磁性粒子选择为大于60，并且磁性层的膜厚度落在平均晶粒尺寸的两倍内。 因此，可以实现可以降低媒体噪声的磁记录系统，可以获得高S / N和低误码率，并且其具有高达2吉比特每平方英寸的高记录密度和MTBF （故障之间的平均时间）高于30万小时。