Magnetic layer of a magnetic recording disk, and related magnetic recording disks
The present disclosure relates to magnetic recording disks having a magnetic recording layer that includes a plurality of three-dimensional segregant structures. Each three-dimensional segregant structure extends from a first radius of the recording disk to a second radius of the recording disk, and each three-dimensional segregant structure is made of a first segregant material. The magnetic recording layer also includes a plurality of magnetic grains between adjacent three-dimensional segregant structures, and a second segregant material between adjacent magnetic grains. The present disclosure also relates to corresponding methods of manufacturing such a magnetic recording layer.
1 . A magnetic recording disk comprising:
a substrate comprising a central opening, at least a first major surface, and an outermost perimeter, wherein the central opening defines an innermost perimeter of the magnetic recording disk, and wherein the outermost perimeter defines an outside diameter of the magnetic recording disk;
a nucleation layer present on the first major surface; and
a magnetic recording layer present on the nucleation layer, wherein the magnetic recording layer comprises:
a plurality of three-dimensional segregant structures, wherein each three-dimensional segregant structure extends continuously from approximately the innermost perimeter of the magnetic recording disk to approximately the outside diameter of the magnetic recording disk, wherein each three-dimensional segregant structure is made of a first segregant material, wherein each three-dimensional segregant structure has a shape, and wherein the shapes of plurality of three-dimensional segregant structures are a repeating pattern across the magnetic recording layer, wherein each three-dimensional segregant structure has a first sidewall and a second sidewall, wherein the first sidewall and the second sidewall extend from the nucleation layer; and
a plurality of magnetic grains between adjacent three-dimensional segregant structures, wherein the plurality of magnetic grains were sputtered onto the nucleation layer having the plurality of three-dimensional segregant structures, wherein a first plurality of the plurality of magnetic grains are directly adjacent to the first sidewall of each three-dimensional segregant structure and align in as-sputtered form with the first sidewall, and wherein a second plurality of the plurality of magnetic grains are directly adjacent to the second sidewall of each three-dimensional segregant structure and align in as-sputtered form with the second sidewall; and
a second segregant material between adjacent magnetic grains that are part of the plurality of magnetic grains between adjacent three-dimensional segregant structures, wherein each of the plurality of three-dimensional segregant structures has a height that corresponds to a thickness of the corresponding three-dimensional segregant structure that overlies the nucleation layer in a direction perpendicular to the first major surface, wherein the second segregant material has a height that corresponds to a thickness of the second segregant material that overlies the nucleation layer in a direction perpendicular to the first major surface, and wherein the height of the second segregant material is greater than the height of each three-dimensional segregant structure.
2 . The magnetic recording disk of claim 1 , wherein each three-dimensional segregant structure has a width of 3 nanometers or less.
3 . The magnetic recording disk of claim 1 , wherein the first segregant material and the second segregant materials are the same.
4 . The magnetic recording disk of claim 1 , wherein each three-dimensional segregant structure has a first surface in contact with the nucleation layer and a second surface opposite the first surface, wherein the second surface of each three-dimensional segregant structure does not have a magnetic grain in contact with the second surface.
5 . The magnetic recording disk of claim 1 , wherein the plurality of three-dimensional segregant structures has a pitch between adjacent three-dimensional segregant structures, wherein the pitch is 30 nanometers or less.
6 . The magnetic recording disk of claim 5 , wherein the pitch between adjacent three-dimensional segregant structures is from 9 to 20 nanometers.
7 . The magnetic recording disk of claim 1 , wherein each three-dimensional segregant structure extends continuously in a path chosen from a linear path, a curvilinear path, and combinations thereof.
8 . The magnetic recording disk of claim 1 , wherein each three-dimensional segregant structure extends continuously in a curvilinear path.
9 . The magnetic recording disk of claim 1 , wherein each three-dimensional segregant structure extends continuously in a linear path.
10 . The magnetic recording disk of claim 1 , wherein each three-dimensional segregant structure has a width from 0.1 nanometers to less than 3 nanometers.
11 . The magnetic recording disk of claim 1 , wherein each three-dimensional segregant structure has a width of 2 nanometers or less.
12 . The magnetic recording disk of claim 1 , wherein the first segregant material is chosen from oxides, nitrides, carbides, and mixtures thereof.
13 . The magnetic recording disk of claim 1 , wherein the first segregant material is chosen from BN, BC, C, SiC, SiN, TIC, TIN, CrN, TiO 2 , Al 2 O 3 , Nb 2 O 5 , SiO 2 , MoO 3 , Cr 2 O 3 , Ta 2 O 5 , ZrO 2 , V 2 O 5 , WO 3 , Y 2 O 3 , and mixtures thereof.
14 . The magnetic recording disk of claim 1 , wherein the first segregant material and the second segregant material are different.
15 . The magnetic recording disk of claim 1 , wherein the height of each of the plurality of three-dimensional segregant structures is 10 nanometers or less.
16 . The magnetic recording disk of claim 1 , wherein the height of each of the plurality of three-dimensional segregant structures is 5 nanometers or less.
17 . The magnetic recording disk of claim 1 , wherein the height of each of the plurality of three-dimensional segregant structures is 3 nanometers or less.