G11B5/73911

SUBSTRATE FOR MAGNETIC DISKS, AND MAGNETIC DISK
20200027481 · 2020-01-23 ·

A substrate for a magnetic disk includes a substrate main body having two main surfaces, and a film that is provided on the main surfaces and is made of a material having a loss factor of 0.1 or more. The substrate for a magnetic disk including the film has a thickness T of 0.700 mm or less, and a thickness D [mm] of the film provided on the main surfaces and the thickness T [mm] of the substrate for a magnetic disk including the film satisfy a relationship D0.0082/T0.0015.

Sidewall guided directed self assembly data storage medium

A data storage medium may have increased data capacity by being configured with first and second patterned pedestals that are each separated from a substrate by a seed layer. A first polymer brush layer can be positioned between the first and second patterned pedestals atop the seed layer and a second polymer brush layer may be positioned atop each patterned pedestal. The first and second polymer brush layers may be chemically different and a block copolymer can be deposited to self-assemble into separate magnetic domains aligned with either the first or second polymer brush layers.

MAGNETIC RECORDING MEDIUM AND CARTRIDGE
20240170015 · 2024-05-23 ·

Provided is a magnetic recording medium capable of curbing deterioration in electromagnetic conversion characteristics.

A magnetic recording medium with a tape shape includes a substrate that contains polyesters, an underlayer that is provided on the substrate, and a magnetic layer that is provided on the underlayer and contains a magnetic powder. The magnetic recording medium contains a lubricant. An average value of arithmetic average roughnesses Ra of a surface of the magnetic layer is 1.3 nm or less. In a case where an average value of peak half widths of a spacing increase region generated on an entrance side of a glass pseudo head which the magnetic recording medium enters when the magnetic recording medium is slid over the glass pseudo head is set as a spacing index SRL and an average value of peak half widths of a spacing increase region generated in the vicinity of an edge of the magnetic recording medium in a width direction when the magnetic recording medium is slid over the glass pseudo head is set as a spacing index SRT, the spacing index SRL is 35 ?m or less and the spacing index SRT is 68 ?m or less.

Substrate for magnetic disk and magnetic disk
12020735 · 2024-06-25 · ·

A substrate for a magnetic disk has a disk shape. The substrate has a diameter D of 85 mm or more and a thickness T of 0.6 mm or less. When an impact is applied to the substrate under conditions of 70 (G) and 2 (msec) in a normal direction of main surfaces of the substrate in a state in which an inner circumferential end portion of the substrate is fixed, the maximum amplitude of vibration in a thickness direction of an outer circumferential end portion of the substrate is 0.25 mm or less, the substrate is a non-magnetic metal substrate, and regarding the Young's modulus E and the thickness T of the substrate, a value of E.Math.T.sup.3 is 3 to 18 (GPa.Math.mm.sup.3).

RECORDING MEDIUM, METHOD OF MANUFACTURING FULLERENE THIN FILM, RECORDING REPRODUCING APPARATUS, INFORMATION RECORDING METHOD, AND INFORMATION READING METHOD
20180336924 · 2018-11-22 · ·

According to the present invention, there is provided a recording medium comprising a substrate, a platinum layer formed on the substrate and having a (111) plane preferentially oriented, and a fullerene single crystal thin film formed on the platinum layer, and configured to be a recording layer, wherein an average value of average surface roughness Ra's with respect to four or more visual fields measured by using an atomic force microscope in a surface of the fullerene thin film is 0.5 nm or less.

Sidewall Guided Directed Self Assembly Data Storage Medium

A data storage medium may have increased data capacity by being configured with first and second patterned pedestals that are each separated from a substrate by a seed layer. A first polymer brush layer can be positioned between the first and second patterned pedestals atop the seed layer and a second polymer brush layer may be positioned atop each patterned pedestal. The first and second polymer brush layers may be chemically different and a block copolymer can be deposited to self-assemble into separate magnetic domains aligned with either the first or second polymer brush layers.

SUBSTRATE FOR MAGNETIC DISK AND MAGNETIC DISK
20240296867 · 2024-09-05 ·

A substrate for a magnetic disk has a disk shape. The substrate has a diameter D of 85 mm or more and 100 mm or less, and a thickness T of 0.3 mm or more and 0.5 mm or less. Regarding a Young's modulus E and the thickness T of the substrate, a value of E.Math.T.sup.3 is 3 to 18 (GPa.Math.mm.sup.3). A material of the substrate has a Q-value of 1500 or less under conditions of 3000 Hz and room temperature.

Magnetic shift register

This disclosure relates to a memory device that includes at least one magnetic track on a substrate, wherein the at least one magnetic track comprises one or more magnetic domains. Contacts can be disposed on the at least one magnetic track according to a predetermined arrangement to form a plurality of bitcells on the at least one magnetic track, wherein each one of the plurality of bitcells is configured to store at least one magnetic domain. The device can include a timing circuit connected to the contacts, with the timing circuit being configured to apply to the contacts multiple phases of electric currents according to a predetermined timing sequence to cause the at least one magnetic domain to shift from the each one of the plurality of bitcells to an adjacent one of the plurality of bitcells on the at least one magnetic track.

L10-ordered MnAl thin films with high perpendicular magnetic anisotropy, and structures and devices made therewith

A stacked-thin-film structure that includes an Llo-ordered MnAl layer having high perpendicular magnetic anisotropy (PMA). In some embodiments, the Ll0-ordered MnAl layer has an Mn content in a range of about 35% to about 65%, a thickness less than about 50 nm, a saturation magnetization of about 100 emu/cm3 to about 600 emu/cm3 and a magnetocrystalline anisotropy of at least 1?106 erg/cm. In some embodiments, the high-PMA Llo-ordered MnAl material is incorporated in magnetic tunneling junction stacked-film structures that are part of magnetoelectronic circuitry, such as spin-transfer-torque magnetoresistive random access memory circuitry and magnetic logic circuitry. In some embodiments, the high-PMA Llo-ordered MnAl material is incorporated into other devices, such as into read/write heads and/or recording media of hard-disk-drive devices.

Recording medium, method of manufacturing fullerene thin film, recording reproducing apparatus, information recording method, and information reading method

According to the present invention, there is provided a recording medium comprising a substrate, a platinum layer formed on the substrate and having a (111) plane preferentially oriented, and a fullerene single crystal thin film formed on the platinum layer, and configured to be a recording layer, wherein an average value of average surface roughness Ra's with respect to four or more visual fields measured by using an atomic force microscope in a surface of the fullerene thin film is 0.5 nm or less.