公开(公告)号：US20030017369A1

公开(公告)日：2003-01-23

申请号：US10067333

申请日：2002-02-07

Applicant: Hitachi, Ltd.

Inventor： Yoshiyuki Hirayama ,  Hiroyuki Suzuki ,  Hiroyuki Kataoka ,  Yotsuo Yahisa ,  Tetsuya Kanbe

IPC: G11B005/66

CPC classification number: G11B5/66 ,  G11B5/00 ,  G11B5/012 ,  G11B2005/0002 ,  G11B2005/0016

Abstract: A magnetic recording medium having at least two magnetic layers and a non-magnetic intermediate layer held between them. The first magnetic layer (which is closer to the substrate than the non-magnetic intermediate layer) is formed from an alloy composed of Co, Pr, and Cr, with Pt content being 3-9 at %. The second magnetic layer (which is farther from the substrate than the non-magnetic intermediate layer) is formed from a Co-based alloy containing Pt, Cr, and B. The first and second magnetic layers are magnetized in the mutually antiparallel direction in the absence of an applied magnetic field. The magnetic recording medium is characterized by good thermal stability for recording bits, high recording resolution, and low media noise. It is suitable for a magnetic storage for high recording density with high reliability.

Abstract translation: 具有至少两个磁性层和保持在它们之间的非磁性中间层的磁记录介质。 第一磁性层（其比非磁性中间层更靠近基板）由Co，Pr和Cr组成的合金形成，Pt含量为3-9原子％。 第二磁性层（其比非磁性中间层离基板更远）由含有Pt，Cr和B的Co基合金形成。第一和第二磁性层在相互反平行的方向上被磁化 不存在施加的磁场。 磁记录介质的特征在于用于记录位的良好热稳定性，高记录分辨率和低介质噪声。 适用于具有高可靠性的高记录密度的磁存储。

公开(公告)号：US20030203239A1

公开(公告)日：2003-10-30

申请号：US10413481

申请日：2003-04-15

Applicant: Hitachi, Ltd.

Inventor： Tetsuya Kanbe ,  Yuzuru Hosoe ,  Ichiro Tamai ,  Yoshio Takahashi ,  Kiwamu Tanahashi ,  Satoshi Matsunuma ,  Yoshihiro Shiroishi

IPC: B32B009/00

CPC classification number: G11B5/70 ,  G11B5/714 ,  Y10S428/90

Abstract: In a magnetic storage device, comprising a magnetic recording medium, a drive division that drives said magnetic recording medium in the record direction, a recording division and a regeneration division comprises magnetic head a means that the said magnetic head is put on in the relative motion for the said magnetic recording medium, a signal processing means for carrying out signal input to the said magnetic head and output signal regeneration from the said magnetic head, The said magnetic storage device uses a medium that has a following features; a magnetic layer in the said magnetic recording medium is formed on the substrate through monolayer or multiple underlayer, comprises said magnetic recording medium, the said magnetic layer has granular structure that the magnetic crystal grain is separated by the nonmagnetic phase, and the coercive force orientation ratio is bigger than 1. In the approximation that the said magnetic crystal grain is ellipsoid, the area ratio of the crystal grain of which the extended shaft direction is within 30null from circumferential direction is over 45% or c shaft length radialy measured swells over 1% compared to a shaft length circumferentially measured.

Abstract translation: 在磁存储装置中，包括磁记录介质，在记录方向上驱动所述磁记录介质的驱动分区，记录分区和再生分段，包括磁头a，使所述磁头相对运动 对于所述磁记录介质，信号处理装置用于对所述磁头执行信号输入并输出信号再生。所述磁存储装置使用具有以下特征的介质; 所述磁记录介质中的磁性层通过单层或多层下层形成在基板上，包括所述磁记录介质，所述磁性层具有磁结晶粒由非磁性相分离的颗粒结构，矫顽力取向 比率大于1.在近似所述磁晶粒为椭圆体的情况下，延伸轴方向与圆周方向相距在30°以内的晶粒的面积比超过45％或c轴长度的径向测量膨胀 相对于圆周测量的轴长度为1％。

公开(公告)号：US20040028950A1

公开(公告)日：2004-02-12

申请号：US10631768

申请日：2003-08-01

Applicant: Hitachi, Ltd.

Inventor： Tetsuya Kanbe ,  Yotsuo Yahisa ,  Yosibumi Matsuda ,  Jo Inagaki ,  Koji Sakamoto

IPC: H01F001/00

CPC classification number: G11B5/7325 ,  G11B5/00 ,  G11B5/656 ,  Y10S428/90 ,  Y10T428/12465 ,  Y10T428/12854 ,  Y10T428/12944

Abstract: The longitudinal magnetic recording medium includes a non-magnetic substrate, a first underlayer having at least one of an amorphous structure and a fine crystal structure formed on the non-magnetic substrate, a second underlayer having a body-centered cubic structure formed on the first underlayer, a third underlayer having a hexagonal closed packed structure formed on the second underlayer, and a magnetic layer having the hexagonal closed packed structure formed on the third underlayer, wherein the third underlayer is composed of an alloy containing Co and Ru.

Abstract translation: 所述纵向磁记录介质包括非磁性基板，在非磁性基板上形成非晶体结构和微细晶体结构中的至少一个的第一底层，在第一基底上形成的体心立方结构的第二底层 底层，形成在第二底层上的具有六方密闭填充结构的第三底层和形成在第三底层上的具有六方密闭填充结构的磁性层，其中第三底层由含有Co和Ru的合金构成。

公开(公告)号：US20030138665A1

公开(公告)日：2003-07-24

申请号：US10306361

申请日：2002-11-27

Applicant: Hitachi, Ltd.

Inventor： Tetsuya Kanbe ,  Yotsuo Yahisa ,  Hiroyuki Suzuki ,  Hidekazu Kashiwase

IPC: B32B009/00

CPC classification number: G11B5/7325 ,  G11B5/66 ,  Y10S428/90 ,  Y10T428/12465 ,  Y10T428/12854 ,  Y10T428/265

Abstract: An inplane magnetic recording medium having high S/N and thermal stability and a reliable magnetic storage device having surface recording density of 50 megabit/mm2 or more is described. The magnetic recording medium includes magnetic layers formed on a nonmagnetic substrate with a plurality of ground layers therebetween, at least one of the ground layers formed from an alloy of a body-centered cubic structure containing Cr as a main component and B of from 2 atomic % to 12 atomic %. Main components of the magnetic layers include a lower magnetic layer containing Co and Cr of from 10 atomic % to 16 atomic %, with film thickness of from 1.5 nm to 4.5 nm, and an upper magnetic layer containing Co, coupling anti-ferromagnetically with the lower magnetic layer through nonmagnetic intermediate layers.

Abstract translation: 描述了具有高S / N和热稳定性的内置磁记录介质和具有50兆比特/平方毫米或更大的表面记录密度的可靠的磁存储装置。 磁记录介质包括形成在非磁性基底上的磁性层，其间具有多个接地层，至少一个接地层由以Cr为主要成分的体心立方结构的合金形成，B为2原子 ％至12原子％。 磁性层的主要成分包括含有10原子％〜16原子％的Co和Cr的下部磁性层，膜厚为1.5nm〜4.5nm，上部磁性层为Co，与铁素体 通过非磁性中间层降低磁性层。

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。