公开(公告)号：US20170256278A1

公开(公告)日：2017-09-07

申请号：US15603964

申请日：2017-05-24

Applicant: HOYA CORPORATION

Inventor： Takashi MAEDA ,  Takumi KUHARA

IPC: G11B5/73 ,  G11B5/82

CPC classification number: G11B5/73 ,  G11B5/7315 ,  G11B5/82

Abstract: When waviness having a wavelength component of 10 to 500 μm in the circumferential direction of a main surface of a disk-shaped substrate is acquired and slopes are acquired from the waviness at an interval of 50 to 100 μm, the substrate being used in a magnetic disk on which recording or reading is performed using a DFH head, an average value of absolute values of the slopes is 0.45×10−4 or less. This magnetic-disk substrate is used in a magnetic disk and a magnetic-disk drive device.

公开(公告)号：US20160329073A1

公开(公告)日：2016-11-10

申请号：US15107764

申请日：2014-12-26

Applicant: HOYA CORPORATION

Inventor： Takashi MAEDA ,  Takumi KUHARA

IPC: G11B5/73 ,  G11B5/82

CPC classification number: G11B5/73 ,  G11B5/7315 ,  G11B5/82

Abstract: When waviness having a wavelength component of 10 to 500 μm in the circumferential direction of a main surface of a disk-shaped substrate is acquired and slopes are acquired from the waviness at an interval of 50 to 100 μm, the substrate being used in a magnetic disk on which recording or reading is performed using a DFH head, an average value of absolute values of the slopes is 0.45×10−4 or less. This magnetic-disk substrate is used in a magnetic disk and a magnetic-disk drive device.

Abstract translation: 在圆盘状基板的主面的圆周方向上取波长成分为10〜500μm的波纹，以波纹为50〜100μm的范围获得斜率，将该基板用于磁性 使用DFH头进行记录或读取的盘，斜率的绝对值的平均值为0.45×10 -4以下。 该磁盘基板用于磁盘和磁盘驱动装置。

公开(公告)号：US20140287269A1

公开(公告)日：2014-09-25

申请号：US14299881

申请日：2014-06-09

Applicant: HOYA CORPORATION

Inventor： Shinji EDA ,  Hideki ISONO ,  Takashi MAEDA ,  Hiroshi TSUCHIYA ,  Yoshinori MARUMO

IPC: G11B5/73

CPC classification number: C03C23/009 ,  C03C19/00 ,  C03C21/008 ,  C03C23/0075 ,  C03C2204/08 ,  C09G1/02 ,  G11B5/7315 ,  G11B5/8404 ,  G11B5/8408

Abstract: Provided are a magnetic disk substrate and a method of manufacturing the same, wherein the magnetic disk substrate has very few defects present on its surface with an arithmetic mean roughness (Ra) at a level in the vicinity of 0.1 nm and thus is suitable as a substrate for a magnetic disk with high recording density. The magnetic disk glass substrate is such that the arithmetic mean roughness (Ra) of the main surface of the glass substrate measured using an atomic force microscope with a resolution of 256×256 pixels in a 2 μm×2 μm square is 0.12 nm or less and the number of defects detected to have a size of 0.1 μm to 0.6 μm in plan view and a depth of 0.5 nm to 2 nm is less than 10 per 24 cm2, wherein the defects are each detected using a shift in wavelength between incident light and reflected light upon irradiating and scanning helium neon laser light with a wavelength of 632 nm on the main surface of the glass substrate.

Abstract translation: 提供一种磁盘基板及其制造方法，其中，磁盘基板的表面上存在极少的缺陷，算术平均粗糙度（Ra）在0.1nm附近，因此适合作为 具有高记录密度的磁盘的基板。 磁盘玻璃基板使用原子力显微镜在2μm×2μm的正方形中以256×256像素的分辨率测量的玻璃基板的主面的算术平均粗糙度（Ra）为0.12nm以下 并且在平面图中检测为具有0.1μm至0.6μm的尺寸和0.5nm至2nm的深度的缺陷的数量小于每24cm 2的10个，其​​中每个使用入射光之间的波长偏移检测缺陷 并在玻璃基板的主表面上照射和扫描波长为632nm的氦氖激光的反射光。

公开(公告)号：US20140085750A1

公开(公告)日：2014-03-27

申请号：US14094960

申请日：2013-12-03

Applicant: HOYA CORPORATION

Inventor： Kouji KITSUNAI ,  Takashi MAEDA

IPC: G11B5/73 ,  G11B5/82

CPC classification number: G11B5/7315 ,  G11B5/82

Abstract: A glass substrate for a magnetic disk, wherein, in regions with respect to two places arbitrarily selected on a surface of the glass substrate on its central portion side relative to its outer peripheral end, a surface shape with a shape wavelength in a band of 60 to 500 μm is extracted from surface shapes in each of the regions and, assuming that a root mean square roughness Rq of the surface shape is given as a microwaviness Rq, the difference between the microwavinesses Rq of the regions is 0.02 nm or less or the difference between standard deviations of the microwavinesses Rq of the regions is 0.04 nm or less.

Abstract translation: 一种磁盘用玻璃基板，其特征在于，在相对于其外周端部的中央部侧的玻璃基板的表面上任意选择的两个位置的区域中，形状波长为60nm的波长的表面形状 在每个区域中从表面形状提取至500μm，并且假设表面形状的均方根粗糙度Rq作为微波特性Rq，则区域的微波特性Rq之差为0.02nm以下，或者 区域的微波的标准偏差之间的差异为0.04nm以下。