Magnetic recording medium having Ni-Pt seed layer

Abstract

A magnetic recording medium is described that includes a substrate and an amorphous soft underlayer (SUL). A Ni-Pt seed layer is formed on the SUL in which Pt atoms have substituted at least some of the Ni atoms within the Ni lattice structure of Ni-Pt to form a solid solution of Ni-Pt. In some examples, the Ni-Pt seed layer is formed from Ni40Pt60. A Ru intermediate layer is formed on the seed layer. In some examples, the lattice mismatch of the Ni-Pt seed layer and the Ru intermediate layer is 0.4% or less. A magnetic recording layer is formed on the Ru intermediate layer. Additional layers or films may be provided. The media may be configured for use with perpendicular magnetic recording (PMR). A data storage device is described that includes the magnetic recording medium. Methods for manufacturing the magnetic recording media are also described herein.

Description

Technical Field

[0001] This disclosure relates in various aspects to magnetic recording media, and more specifically to the design of magnetic recording media for perpendicular magnetic recording. Background Technology

[0002] Magnetic storage systems, such as hard disk drives (HDDs), are used in a variety of devices in both static and mobile computing environments. Examples of devices incorporating magnetic storage systems include data center storage systems, desktop computers, laptop computers, portable hard disk drives, network storage systems, high-definition television (HDTV) receivers, vehicle control systems, cellular or mobile phones, set-top boxes, digital cameras, digital video cameras, video game consoles, and portable media players.

[0003] Many magnetic recording disks used in HDDs are configured for perpendicular magnetic recording (PMR). PMR, also known as conventional magnetic recording (CMR), operates by aligning the magnetic poles of the magnetic elements of the magnetic recording layer (MRL) perpendicular to the surface of the disk. The magnetic elements represent data bits. PMR disk designs often include seed layers to produce growth templates for films subsequently deposited within the recording disk, comprising one or more ruthenium (Ru)-based intermediate layers and MRLs, and to provide the correct crystallographic orientation within the Ru intermediate layers and MRLs, for example, a hexagonal close-packed (HCP) crystal structure, such as HCP(0001).

[0004] It is desirable to provide improvements within the seed layer of a PMR medium or other magnetic recording media to provide, for example, an improvement in the areal density capacity (ADC) of the disk. Various aspects of this disclosure are directed to these or other purposes. Summary of the Invention

[0005] The following is a brief overview of some aspects of this disclosure to provide a basic understanding of these aspects. This overview is not a comprehensive summary of all contemplative features of this disclosure, and is neither intended to identify key or essential elements of all aspects of this disclosure, nor to depict the scope of any or all aspects of this disclosure. Its sole purpose is to present the various concepts of some aspects of this disclosure in a simplified form as a prelude to the more detailed description that follows.

[0006] One aspect of this disclosure provides a magnetic recording medium configured for magnetic recording. The magnetic recording medium includes: a substrate; an amorphous soft magnetic underlayer (SUL) on the substrate; a seed layer on the SUL and comprising nickel-platinum (Ni-Pt), such as a Ni-Pt alloy, wherein Pt atoms have replaced at least some Ni atoms in the Ni lattice structure of the Ni-Pt; an intermediate layer comprising Ru on the seed layer; and a magnetic recording layer (MRL) on the intermediate layer. The Ni-Pt seed layer may be, for example, Ni 40 Pt 60 In some aspects, the lattice mismatch between the Ni-Pt seed layer and the Ru intermediate layer is 1% or less, and in some examples less than 0.4%. The magnetic recording medium may be a PMR medium. Other layers or films may also be provided. A data storage device may be provided, comprising the magnetic recording medium and a recording head configured to write information to the magnetic recording medium.

[0007] Another aspect of this disclosure provides a method for manufacturing a magnetic recording medium. The method includes: providing a substrate; providing an amorphous solid-state medium (SUL) on the substrate; providing a seed layer on the SUL, the seed layer comprising Ni-Pt (e.g., a Ni-Pt alloy), wherein Pt atoms have replaced at least some Ni atoms within the Ni lattice structure of the Ni-Pt; providing an intermediate layer comprising Ru on the seed layer; and providing a magnetic recording medium (MRL) on the intermediate layer. The Ni-Pt seed layer may, for example, be configured as Ni... 40 Pt 60 The magnetic recording medium can be configured as a PMR medium. Other layers or films may also be provided.

[0008] Another aspect of this disclosure provides a magnetic recording medium comprising: a substrate; an amorphous solid ductile ultrastructure (SUL) on the substrate; a seed layer on the SUL; an intermediate layer comprising Ru on the seed layer, wherein the lattice mismatch between the seed layer and the intermediate layer is 1% or less; and a magnetic resonance ductile layer (MRL) on the intermediate layer. The seed layer may be, for example, Ni. 40 Pt 60 The magnetic recording medium can be configured as a PMR medium. Other layers or films may also be provided. A data storage device can be provided, comprising the magnetic recording medium and a recording head configured to write information to the magnetic recording medium.

[0009] These and other aspects of this disclosure will become more fully understood upon reading the following detailed description. Other aspects, features, and embodiments of this disclosure will become apparent to those skilled in the art after reading the following description of specific embodiments of this disclosure in conjunction with the accompanying drawings. Although features of this disclosure may be discussed with respect to certain embodiments and drawings below, all embodiments of this disclosure may include one or more of the advantageous features discussed herein. In other words, while one or more embodiments may be discussed as having certain advantageous features, one or more of these features may also be used in accordance with the various embodiments of this disclosure discussed herein. Similarly, although certain embodiments may be discussed below as embodiments of an apparatus, a system, or a method, it should be understood that such embodiments may be implemented in various apparatuses, systems, and methods. Attached Figure Description

[0010] The specific aspects illustrated below with reference to the accompanying drawings include a more specific description. It should be understood that these drawings depict only certain aspects of this disclosure and are therefore not intended to be considered as limiting its scope. The disclosure is described and explained with additional specificity and detail using the drawings, in which:

[0011] Figure 1 An example is given where the lattice constant a is... A face-centered cubic (FCC) Ni lattice, which can be used as a seed layer in PMR magnetic recording media.

[0012] Figure 2 An example is given of the lattice constant α formed using 40% Ni and 60% Pt according to various aspects of this disclosure. FCC Ni-Pt lattice.

[0013] Figure 3 This is a top schematic diagram of a data storage device according to some aspects of the present disclosure, the data storage device being configured for magnetic recording and including a magnetic recording medium having a Ni-Pt seed layer.

[0014] Figure 4 Based on some aspects of this disclosure Figure 3 A schematic cross-sectional side view of selected components of a data storage device, which includes a magnetic recording medium having a Ni-Pt seed layer, wherein Pt atoms have replaced Ni atoms.

[0015] Figure 5 This is a schematic cross-sectional side view of a magnetic recording medium having a Ni-Pt seed layer according to some aspects of this disclosure.

[0016] Figure 6This is a graph illustrating the lattice parameter a in angstroms for various FCCNi-Pt seed layers with different percentages of Pt in Ni-Pt according to some aspects of this disclosure, wherein the data are obtained from in-plane X-ray diffraction measurements.

[0017] Figure 7 This is a schematic side cross-sectional view of a portion of a magnetic recording medium having a set of gradient Ni-Pt seed layers between an amorphous SUL and a Ru-based IL, according to some aspects of this disclosure.

[0018] Figure 8 This is a flowchart of a process for manufacturing a magnetic recording medium having a Ni-Pt seed layer, according to some aspects of this disclosure, wherein Pt atoms have replaced Ni atoms.

[0019] Figure 9 This is a side view of an exemplary magnetic recording medium having a Ni-Pt seed layer according to another aspect of the present disclosure, wherein Pt atoms have replaced Ni atoms.

[0020] Figure 10 This is a side view of another exemplary magnetic recording medium having a Ni-Pt seed layer according to another aspect of the present disclosure, wherein Pt atoms have replaced Ni atoms.

[0021] Figure 11 This is a side view schematic diagram of another exemplary magnetic recording medium according to various aspects of this disclosure. Detailed Implementation

[0022] In the following description, specific details are set forth to provide a thorough understanding of various aspects of this disclosure. However, it will be understood by those skilled in the art that various aspects may be implemented without these specific details. For example, circuits may be shown in block diagrams to avoid unnecessarily obscuring the aspects. In other instances, well-known circuits, structures, and techniques may not be shown in detail so as not to hinder the understanding of various aspects of this disclosure.

[0023] This disclosure primarily describes perpendicular magnetic recording (PMR) devices and magnetic recording media. However, at least some aspects of this disclosure can also be applied to other magnetic recording systems, such as heat-assisted magnetic recording (HAMR), in which heat is used to assist in writing data into the magnetic recording medium. It should be noted that HAMR is a type of energy-assisted magnetic recording (EAMR), a broad term encompassing both HAMR and microwave-assisted magnetic recording (MAMR). Systems utilizing energy-assisted recording within PMR media can be referred to as ePMR systems.

[0024] State-of-the-art PMR media include media stack designs that incorporate particle magnetic recording layers (MRLs), which are typically composed of a monolithic array of CoPtOx-based ferromagnetic and isolated particles for storing magnetic information or bits. These materials, in thin film form, possess a hexagonal close-packed (HCP) crystal structure with a preferred (0001) texture and are typically deposited on one or more Ru-based intermediate layers (ILs) of nonmagnetic HCPs, the dome-shaped top surfaces of which facilitate the particle morphology of the PMR media stack.

[0025] Within the PMR stack, a seed layer is provided, typically very thin (approximately 2.0 nm to 3.0 nm) and deposited on an amorphous and ferromagnetic soft underlayer (SUL) covering an AlMg or glass substrate. The seed layer provides a structural template for the crystal growth of Ru-based ILs of HCPs, which in turn provide a template for the crystal growth of HCP MRLs. Typical seed layer materials belong to the family of nickel-based (Ni) or Ni-Fe-based alloys with a face-centered cubic (FCC) crystal structure (e.g., NiFeWAl). Due to the preferred (111) orientation of the crystallographic texture of the seed layer, it facilitates the desired HCP crystal configuration of the Ru-based ILs and the CoPtOx-based MRL films deposited on these Ru-based ILs.

[0026] Half of the interatomic distance in the

[111] plane of a typical Ni-Fe seed layer is approximately Therefore, the seed layer and Ru-based IL (with approximately The lattice mismatch between the Ru-IL and the in-plane lattice constant is non-negligible and is, for example, about 7%. It is possible to provide an additional Ru-based pre-intermediate layer (pre-IL) between the Ni-based or Ni-Fe-based seed layer and the Ru-IL to reduce the lattice mismatch and improve the crystallinity of the Ru-IL and MRL layers. For example, by adding multiple pre-IL films with different compositions, the in-plane lattice constant can be increased from that of the seed layer (approximately 7%). Gradually changing to Ru-IL (approximately) However, this increases the cost and the overall thickness of the underlying layer under the MRL.

[0027] In this paper, the seed layer is alternatively described as having an FCC crystal structure but with a larger lattice parameter in order to minimize the lattice mismatch between the seed layer and the Ru-based IL. The disclosed seed layer (1) helps to improve the crystallographic ordering and orientation of the Ru-based IL and MRL grains, and (2) allows for dielectric designs with reduced SUL-MRL spacing by reducing the thickness of the bottom layer of the PMR stack, thereby resulting in improved writability and / or reduced grain pitch. The resulting lattice mismatch can be less than 1%, and in some examples, the lattice mismatch is 0.2% or less.

[0028] In some aspects, the seed layer consists of Ni doped with platinum (Pt) to provide a Ni-Pt layer (e.g., Ni 40 Pt 60 In this structure, Pt atoms have replaced at least some of the Ni atoms in the Ni lattice structure of Ni-Pt. Pt is used as a seed layer dopant for at least three reasons: (1) Pt has a larger atomic radius than pure Ni, which increases the lattice parameters of the seed layer (thus reducing lattice mismatch with Ru IL); (2) Pt is completely soluble in Ni (at least at the temperatures associated with the fabrication and operation of the PMR medium) and thus maintains a single FCC phase (which helps preserve and promote the HCP structure of Ru IL and MRL); and (3) Pt can reduce the total magnetic moment of the seed layer, which is important for controlling the performance of cross-track magnetic recording.

[0029] It should be noted that the increasing doping concentration in Pt to Ni leads to a monotonically expanding FCC cubic lattice, thereby minimizing the aforementioned lattice mismatch between the seed layer film and the Ru-based IL film. Furthermore, compared to NiFeWAl seed layers, Ni-Pt seed layers significantly enhance the crystallographic and morphological properties of the MRL grains at a given grain pitch. This results in an improved intrinsic signal-to-noise ratio (SNR) and thus an improved areal density capacity (ADC) in magnetic recording. (It should also be noted that Ni-Pt can also be referred to as NiPt or other suitable abbreviations).

[0030] In this paper, solubility refers to solid-state solubility, where the Ni-Pt seed layer is considered a solid solution. A solid solution is a homogeneous mixture of two different kinds of atoms in the solid state and having a single crystal structure. In this context, the term "solution" refers to a homogeneous mixture of Ni and Pt at the atomic level, and is distinct from a purely physical mixture of Ni and Pt. Generally, solid solutions can exist between two isomorphic compounds. Ni and Pt are isomorphic. In this context, Ni is the solvent and Pt is the solute.

[0031] Generally, a solute (e.g., Pt) can be incorporated into a solvent lattice (e.g., a Ni lattice) either substitutively (by replacing solvent particles in the lattice) or interstitially (by fitting into the spaces between solvent particles). In this document, the solubility described is substitutional, meaning that Pt atoms replace some Ni atoms within the Ni lattice. Because the atomic radius of Pt is larger than that of Ni, the unit cell of the lattice expands to accommodate Pt. This miscibility is achieved through… Figure 1 and Figure 2 As shown.

[0032] Figure 1 An example is FCC Ni lattice 100 without Pt. That is, Figure 1 The crystal lattice is Ni 100 As shown in the figure, the lattice constant is

[0033] Figure 2 An example is shown: an FCC solid solution Ni-Pt lattice 200 with 40% Ni and 60% Pt, where the percentages are atomic percentages (at.%). As shown in the figure, the resulting lattice constant is... In other words, Ni 40 Pt 60 Its lattice constant is greater than that of Ni 100 The lattice constant. A larger lattice constant is used to reduce the lattice mismatch between the seed layer and the Ru-based IL grown on the seed layer (and...). Figure 1 (Compared to only the Ni lattice). It should be noted that in Figure 2 In this structure, Pt atoms have replaced Ni atoms within the Ni lattice, while maintaining the same FCC structure. If Pt is insoluble in Ni (e.g., by having different phases), then Pt atoms can alternatively act as Ni isolates, or if the solubility of Pt within the Ni lattice is interstitial rather than substitutive, then Pt atoms will disrupt the FCC structure. It should also be noted that the seed layer is an example of pure Pt without Ni (i.e., Pt...). 100 In this case, the lattice constant will be

[0034] Therefore, in one aspect, this document describes a magnetic recording medium comprising: a substrate; an amorphous solid-state lattice (SUL) on the substrate; and a Ni-Pt seed layer on the SUL, wherein Pt atoms have replaced at least some Ni atoms within the Ni lattice structure of the Ni-Pt. A Ru intermediate layer (RuIL) is on the seed layer. An intermediate layer (MRL) is formed on the Ru intermediate layer. Additional layers may be provided. Methods for manufacturing this magnetic recording medium are also described herein.

[0035] In another aspect, this document describes a magnetic recording medium comprising: a substrate; an amorphous solid lattice element (SUL) on the substrate; and a seed layer on the SUL. A Ru IL is located on the seed layer, wherein the lattice mismatch between the seed layer and the Ru IL is 1% or less, for example, 0.4% or less. An MRL is formed on the Ru IL. The seed layer may be Ni-Pt. Additional layers may be provided. Methods for manufacturing this magnetic recording medium are also described herein.

[0036] Among other advantages, the magnetic recording medium described herein can be used to: (1) provide improved crystallization ordering and orientation of Ru-based IL and MRL grains at a given grain pitch compared to conventional seed layers (e.g., NiFeWAl seed layers); (2) provide improved surface roughness of the magnetic recording medium at a given grain pitch compared to conventional seed layers; and (3) provide improved SNR for both untuned (on the track) and tuned (on the track) at a given track width compared to conventional seed layers. Furthermore, by using Ni… 40 Pt 60 Seed layers, when using conventional seed layers (e.g., NiFeWAl seeds), can achieve smaller center-to-center (CTC) spacing matching values ​​for Hc (coercive field) and KuV / kT (thermal stability factor). This is likely due to improved crystal ordering. (Note that in "KuV / kT", Ku represents the anisotropy constant, V represents the volume, k represents the Boltzmann constant, and T represents the absolute temperature.)

[0037] Exemplary Examples and Implementation Schemes

[0038] Figure 3This is a top schematic diagram of a data storage device (e.g., a disk drive) 300 configured for magnetic recording and comprising a magnetic recording medium 302 having a Ni-Pt seed layer (where Pt atoms have replaced at least some of the Ni atoms in the Ni lattice structure of Ni-Pt), a Ru-based IL, and a MRL. In the primary example described herein, the magnetic recording medium 302 is configured as a PMR medium. The disk drive 300 may include one or more disks / media 302 for storing data. The disks / media 302 reside on a spindle assembly 304, which is mounted to a drive housing 306. Data may be stored along tracks 307 in the magnetic recording layer of the disk 302. Reading and writing of data are accomplished using a head / slider 308 which may have both read and write elements. The write elements are used to change the magnetization direction of a portion of the magnetic recording layer of the disk 302, and thus write information to that portion. The read / write head 308 may have magnetoresistive (MR) based elements, such as tunneling magnetoresistive (TMR) for reading, and write poles with coils energized for writing. In operation, a spindle motor (not shown) rotates the spindle assembly 304, thereby rotating the disk 302 to position the read / write head 308 at a specific location along the desired disk track 307. The position of the read / write head 308 relative to the disk 302 can be controlled by the position control circuitry 310 of the disk drive 300.

[0039] Figure 4 It includes a magnetic recording medium 402 with a Ni-Pt seed layer (corresponding to...) Figure 3 Disk / media 302) Figure 3 A schematic cross-sectional side view of selected components of the data storage device (where Pt atoms have replaced at least some of the Ni atoms within the Ni lattice structure of Ni-Pt). Magnetic head / slider 408 (corresponding to...) Figure 3 The magnetic head 308 is located above the medium 302. The magnetic head / slider 408 includes a write element and a read element (not shown) positioned along the air bearing surface (ABS) (e.g., the bottom surface) of the slider for writing information to and reading information from the medium 402. Figure 3 and Figure 4 Specific examples of magnetic recording systems are illustrated. In other examples, the improved media embodiments with Ni-Pt seed layers disclosed herein can be used in any suitable magnetic recording system. For simplicity, the various embodiments are described primarily in the context of the example HDD magnetic recording system.

[0040] Figure 5 It is possible to be with Figure 3 and Figure 4A schematic cross-sectional side view of a magnetic recording medium 500 with a Ni-Pt seed layer used in conjunction with a disk drive 300. In the primary example described herein, the magnetic recording medium 500 is configured for PMR. The magnetic recording medium 500 has a stacked structure. In order from bottom to top, the medium 500 includes a substrate 502, an amorphous SUL 504, a Ni-Pt seed layer 506 (where Pt atoms have replaced at least some Ni atoms in the Ni lattice structure of Ni-Pt), a Ru-based intermediate layer 508, a bottom layer 510, an MRL structure 512, and an outer cover layer 514. In some examples, the MRL structure 512 has multiple magnetic recording layers and multiple non-magnetic exchange control layers (ECLs). Additional layers or films may be provided.

[0041] The substrate 502 may be made of one or more materials, such as aluminum (Al) alloys, nickel-phosphorus (NiP) plated Al, glass, glass ceramics, and / or combinations thereof. In one embodiment, the substrate 502 may be a rigid substrate (e.g., glass or ceramic).

[0042] The amorphous SUL 504 can be made of one or more ferromagnetic materials (such as cobalt (Co), iron (Fe), molybdenum (Mo), tantalum (Ta), niobium (Nb), boron (B), chromium (Cr), or other soft magnetic materials, or combinations thereof) having high permeability, high saturation magnetization, and low coercivity. The amorphous SUL 504 may comprise an amorphous compound with one or more nonmagnetic elements selected from Mo, Nb, Ta, W, and B, or a combination of Co and Fe (e.g., a CoFe alloy). The SUL 504 can be configured to support magnetization of the magnetic recording layer structure 512 during data storage operations. More specifically, the amorphous SUL 504 can be configured to provide a return path to the magnetic field applied during write operations.

[0043] The thickness of amorphous SUL 504 ranges from 80 angstroms to 180 angstroms. In one embodiment, the thickness of amorphous SUL 504 is 150 angstroms.

[0044] The seed layer 506 can be Ni-Pt, wherein Pt atoms have replaced at least some of the Ni atoms in the Ni lattice structure of Ni-Pt. The atomic percentage of Pt in Ni-Pt can be, for example, in the range of 20 at.% to 90 at.%, or in the range of 40 at.% to 80 at.%, or in the range of 50 at.% to 70 at.%, or in some examples, Pt is 60 at.%, for example, in a compound of Ni. 40 -Pt 60In other examples, Pt is 50 at.% or more, and in some examples, Pt can be 100%, meaning the seed layer is pure Pt without Ni.

[0045] The seed layer 506 has a lattice structure and crystallographic orientation that can determine the crystallographic orientation of the layer (e.g., Ru-based IL 508) grown / deposited on the seed layer 506. In some aspects, the seed layer has an FCC crystallographic structure in which the (111) plane is parallel to the film surface. In some examples, the Ni-Pt of the seed layer has half the interatomic distance of its

[111] plane in the range of 2.5 Å to 2.7 Å. The Ni-Pt of the seed layer may be configured to have a lattice mismatch of 5% or less with Ru-based IL 508, or 1% or less in other examples, or 0.4% or less in other examples. In some aspects, the Ni-Pt seed layer 506 does not contain any oxides (or, if any oxides are present, they are minimal impurities). In some aspects, the seed layer is substantially composed of Ni-Pt. In this document, “substantially composed of Ni-Pt” means that the material composition of the seed layer is at least 99% Ni-Pt. In some examples, the thickness of the seed layer 506 ranges from 20 angstroms to 40 angstroms.

[0046] In some examples, seed layer 506 comprises two or more seed layers with Ni-Pt, each seed layer having a different percentage of Pt atoms; for example, the percentage of atoms may gradually increase as the Pt percentage approaches that of Ru-based IL. (See discussion below) Figure 7 ).

[0047] Figure 6 Figure 600 illustrates the lattice parameter α in angstroms for various FCC seed layers, including those with different percentages of Pt in Ni-Pt substituted alloys. As shown, the lattice parameter α for a seed layer with pure Ni is approximately... (See also) Figure 1 The lattice parameters of the seed layer formed from Ni-Fe-X (where X is, for example, WAl) are approximately... Figure 600 also provides the lattice parameters for various Ni-Pt compositions. Line 602 indicates approximately... The in-plane lattice constant of Ni in the HCP Ru plane. As shown in the figure, Ni 40 Pt 60 lattice parameters Allowing its

[111] interatomic distance (approximately Half of the Ru-IL plane lattice constant (approximately) Half of it is very similar, and therefore a good choice for reducing lattice mismatch.

[0048] Table I provides further information on different Ni-Pt compositions, in which Ni 40 -Pt 60 It provides a lattice mismatch of only 0.4% relative to Ru.

[0049]

[0050] Table I

[0051] Now return to Figure 5 Ru-based IL 508 can contain pure Ru. In other examples, Ru-based IL 508 can contain Ru and other compounds. For example, IL 508 can be CoCrRu and CoCrRuW. The specific amount of W to be used in IL 508 may depend on the materials and configuration of adjacent layers and the relative amounts of Co, Cr, and Ru in the intermediate layers. Ru-based IL 508 can contain, for example, 50% Co, 25% Cr, and 25% Ru (Co50Cr25Ru25) and 45% Co, 25% Cr, 25% Ru, and 5% W (Co45Cr25Ru25W5), where the corresponding percentages are atomic percentages.

[0052] It should be noted that the lattice parameters of the IL layer containing Ru and additional elements (such as Co, Cr, and W) can differ from those of a pure Ru IL layer. Therefore, the choice of Ni-Pt seed layer composition can vary. That is, it can differ from the composition using Ni… 40 Pt 60 Such as Ni 60 Pt 40 Different Ni-Pt compositions can provide a better match with Ru-based ILs to reduce lattice mismatch. Therefore, in some examples, the optimal or preferred Ni-Pt seed composition can be determined by measuring or otherwise identifying the lattice constant of a specific IL composition to be used and then comparing that lattice constant with the data in Table I to determine the best match for the Ni-Pt composition. It should be noted that Ni-Pt compositions are not limited to the examples in Table I. The relative atomic percentage can be set to any suitable value, such as, for example, Ni 42 Pt 58 or Ni 49 Pt 51 wait.

[0053] In some embodiments, the optional bottom layer 510 may be made of one or more materials such as Ru and / or other suitable materials known in the art.

[0054] MRL 512 can be made of CoPt or an alloy selected from Co-Pt-X, where X is a material selected from Cr and various oxides and combinations thereof. In some examples, the crystallographic orientation of MRL 314 can promote PMR.

[0055] The outer coating 514 may be made of one or more materials such as carbon (C) and / or other suitable materials known in the art. In one embodiment, the medium 500 may also include a lubricant layer on the outer coating. In such cases, the lubricant layer may be made of one or more materials such as polymer-based lubricants and / or other suitable materials known in the art.

[0056] As described above, in some examples, the Ni-Pt seed layer (e.g., seed layer 506) comprises two or more seed layers having Ni-Pt, each seed layer having a different percentage of Pt atoms. For example, the atomic percentage can be gradient, scaled, or otherwise changed to have an increasing percentage of Pt that more closely resembles that of Ru-based ILs. This is in Figure 7 Example in.

[0057] Figure 7 This is a schematic side cross-sectional view of a portion of a magnetic recording medium 700 having a set of gradient Ni-Pt seed layers between an amorphous SUL 704 and a Ru-based IL 708. In this example, the Ni-Pt seed layer 706 comprises: Ni-Pt seed layers directly on the SUL 704. 60 -Pt 40 The first sublayer 7061 is formed; the Ni directly on the first sublayer 7061 50 -Pt 50 The second sublayer 7062 formed; and the Ni directly on the second sublayer 7062 40 -Pt 60 The third sublayer 7063 was formed. Figure 7 This is just one example of a gradient Ni-Pt seed layer, which may have more or fewer sublayers with different relative atomic percentages than in the specific example shown. It should also be noted that, as mentioned above, each sublayer has Pt atoms that substituted for Ni atoms.

[0058] Figure 8 This is a flowchart of a process 800 for manufacturing a magnetic recording medium including a magnetic recording layer structure. In a particular embodiment, process 800 can be used to manufacture the aforementioned magnetic recording medium including medium 302 and / or medium 500.

[0059] At frame 802, the process provides a substrate. The substrate may be made of one or more materials such as Al alloys, NiP-plated Al, glass, glass ceramics, and / or combinations thereof.

[0060] At frame 804, a soft magnetic underlayer (e.g., Figure 5 Amorphous SUL 504 can be made of one or more materials having high permeability, high saturation magnetization, and low coercivity (such as cobalt (Co), iron (Fe), molybdenum (Mo), tantalum (Ta), niobium (Nb), boron (B), chromium (Cr), or other soft magnetic materials, or combinations thereof). Amorphous SUL 504 may contain amorphous compounds with one or more of the elements Mo, Nb, Ta, W, and B added, or a combination of Co and Fe (e.g., CoFe alloy).

[0061] At box 806, a Ni-Pt seed layer is provided on the SUL, wherein Pt atoms have replaced at least some of the Ni atoms in the Ni lattice structure of the Ni-Pt. The atomic percentage of Pt in the Ni-Pt can, for example, range from 20 at.% to 90 at.%, or from 40 at.% to 80 at.%, or from 50 at.% to 70 at.%, or in some examples, Pt is 60 at.%, for example, Ni 40 -Pt 60 In other examples, Pt is 50 at.% or more. The Ni-Pt seed layer can be configured to have a lattice mismatch of 5% or less with the subsequently deposited Ru-based IL, or in other examples, 1% or less, or in other examples, 0.4% or less. For example, a target formed of a Ni-Pt alloy and a sputtering gas such as argon can be used to employ low-power, low-pressure, low-temperature sputtering deposition. Ni-Pt material is ejected from the target and collected on the SUL of the media disk being manufactured to form a Ni-Pt seed layer on the SUL. The relative atomic percentage of the Ni-Pt seed layer on the SUL can be controlled by providing a Ni-Pt alloy to the target having selected atomic percentages of Ni and Pt. For example, if the Ni-Pt target is Ni 40 -Pt 60 , then Ni 40 -Pt 60 The seed layer will be deposited on the SUL. Other suitable deposition techniques can also be used.

[0062] At box 808, a Ru-based intermediate layer is provided on the seed layer.

[0063] At box 810, an underlayer may optionally be provided on the intermediate layer. This underlayer may be made of one or more materials such as Ru and / or other suitable materials known in the art.

[0064] At frame 812, a magnetic recording layer structure is provided on the bottom layer (e.g., Figure 5The MRL structure 512 in the text. In some embodiments, the magnetic recording layer structure has or includes a plurality of non-magnetic ECLs. In one embodiment, an outer coating layer (e.g., ...) may be provided on the magnetic recording layer structure. Figure 5 (outer cladding layer 514).

[0065] In several embodiments, various deposition subprocesses can be used to perform the formation or deposition of various layers of the magnetic recording medium described herein. These deposition subprocesses include, but are not limited to, physical vapor deposition (PVD), direct current (DC) magnetron sputtering deposition, ion beam deposition, radio frequency sputtering deposition, or chemical vapor deposition (CVD), including plasma-enhanced chemical vapor deposition (PECVD), low-pressure chemical vapor deposition (LPCVD), and atomic layer chemical vapor deposition (ALCVD). In other embodiments, other suitable deposition techniques known in the art may also be used.

[0066] In some embodiments, the procedures described herein may execute sequences of actions in different orders. In other embodiments, these procedures may skip one or more of these actions. In other embodiments, one or more of these actions may be performed simultaneously. In some embodiments, additional actions may be performed. For example, in one aspect, the method may include any additional actions required to fabricate the magnetic recording layer structure.

[0067] Additional examples and implementation schemes

[0068] Figure 9 This is a side view schematic diagram of an exemplary magnetic recording medium 900 according to another aspect of the present disclosure. The magnetic recording medium 900 has a stacked structure having a substrate 902, an amorphous SUL 904 on the substrate 902, a seed layer 906 formed of Ni-Pt on the SUL (where Pt atoms have replaced at least some Ni atoms in the Ni lattice structure of Ni-Pt), a Ru-based IL 908 on the seed layer 906, and an MRL 910 on the Ru-based IL 908. The Ni-Pt seed layer 906 can be configured such that the lattice mismatch between the seed layer and the Ru-based intermediate layer 908 is 1% or less. The Ni-Pt seed layer can be, for example, Ni 40 Pt 60 The magnetic recording medium 900 can be a PMR medium. Other layers or films, as described above, may also be provided.

[0069] Figure 10This is a side view schematic diagram of an exemplary magnetic recording medium 1000 according to another aspect of this disclosure. The magnetic recording medium 1000 has a stacked structure having a substrate 1002, an amorphous SUL 1004 on the substrate 1002, a Ni-Pt seed layer 1006 on the SUL 1004, a Ru-based IL 1008 on the seed layer 1006, and an MRL 1010 on the Ru-based IL 1008. The lattice mismatch between the seed layer 1006 and the Ru-based intermediate layer 1008 is 1% or less, for example, less than 0.4%. This can be achieved, for example, by configuring the Ni-Pt seed layer 1006 so that the Pt atoms are in an appropriate relative ratio of Ni to Pt (such as Ni... 40 Pt 60 This is achieved by substituting Ni atoms. The magnetic recording medium 1000 can be a PMR medium. Other layers or films, as described above, may also be provided.

[0070] Figure 11 This is a flowchart of a process 1100 for manufacturing a magnetic recording medium according to some aspects of this disclosure. In one aspect, process 1100 can be used to manufacture the aforementioned... Figure 9 and Figure 10 The described medium. In block 1102, the process provides a substrate. In block 1104, the process provides an amorphous SUL on the substrate. In block 1106, the process provides a Ni-Pt seed layer on the SUL, wherein Pt atoms have replaced at least some of the Ni atoms in the Ni lattice structure of Ni-Pt, and / or the in-plane lattice constant of the seed layer differs from the in-plane lattice constant of the Ru-based intermediate layer by 1% or less. In block 1108, the process provides a Ru-based IL on the seed layer. In block 1110, an MRL is provided on the Ru-based IL. The fabricated medium may be a PMR medium. In other examples, more or fewer layers may be formed or otherwise provided.

[0071] Additional aspects and considerations

[0072] As used herein, the terms "above," "below," and "between" refer to the relative position of a layer with respect to other layers. Therefore, a layer deposited or disposed above or below another layer may be in direct contact with that layer, or may have one or more intermediate layers. Furthermore, a layer deposited or disposed between layers may be in direct contact with the layers, or may have one or more intermediate layers.

[0073] While the above description includes many specific embodiments, these should not be construed as limiting the scope of the invention, but rather as examples of specific embodiments. Therefore, the scope of the invention should not be determined by the illustrated embodiments, but rather by the appended claims and their equivalents.

[0074] The various features and processes described above can be used independently of each other or combined in various ways. All possible combinations and sub-combinations are intended to fall within the scope of this disclosure. Furthermore, certain methods, events, states, or process blocks may be omitted in some specific embodiments. The methods and processes described herein are not limited to any particular sequence, and the blocks or states associated with them may be executed in other suitable sequences. For example, the described tasks or events may be executed in a different order than that specifically disclosed, or multiple tasks or events may be combined in a single block or state. Example tasks or events may be executed serially, in parallel, or in some other suitable manner. Tasks or events may be added to or removed from the disclosed example embodiments. The example systems and components described herein may be configured differently from those described. For example, elements may be added, removed, or rearranged compared to the disclosed example embodiments.

[0075] The various components described in this specification may be described as "comprising" or being made of certain materials or combinations of materials. In one aspect, this may mean that the component is composed of one or more specific materials. In another aspect, this may mean that the component comprises one or more specific materials.

[0076] As used herein, the term percentage (%) (where the unit is not specified) may be any of weight %, atomic %, mole %, mass % or volume %

[0077] The term “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any specific implementation or aspect described herein as “exemplary” is not necessarily to be construed as being more preferred or advantageous than other aspects of this disclosure. Similarly, the term “aspect” does not require that all aspects of this disclosure include the features, advantages, or modes of operation discussed. The term “coupled” is used herein to refer to direct or indirect coupling between two objects. For example, if object A physically touches object B, and object B touches object C, then object A and object C can still be considered coupled to each other (even if they do not directly and physically touch each other). It should also be noted that, in the context of one component being above another component, the term “above” as used herein can be used to refer to a component on and / or in another component (e.g., on the surface of the component or embedded in the component). Thus, for example, a first component above a second component can refer to (1) the first component on the second component but not in direct contact with the second component, (2) the first component on the second component (e.g., on the surface of the second component), and / or (3) the first component in the second component (e.g., embedded in the second component). As used in this disclosure, the term "about 'value X'" or "approximately value X" should mean within 10% of "value X". For example, a value of about 1 or approximately 1 would mean a value in the range of 0.9–1.1. Various value ranges may be specified, described, and / or claimed in this disclosure. It should be noted that any time a range is specified, described, and / or claimed in the specification and / or claims, it refers to including the end values ​​(at least in one embodiment). In another embodiment, the range may not include the end values ​​of the range. Various values ​​(e.g., value X) may be specified, described, and / or claimed in this disclosure. In one embodiment, it should be understood that value X can be exactly equal to X. In one embodiment, it should be understood that value X can be "about X" having the meaning described above.

Claims

1. A magnetic recording medium, comprising: a substrate; an amorphous soft magnetic underlayer (SUL) on the substrate; a seed layer on the SUL and comprising Ni-Pt, wherein Pt atoms have substitutionally replaced at least some of Ni atoms within a Ni lattice structure of the Ni-Pt; an intermediate layer comprising Ru on the seed layer; and a magnetic recording layer (MRL) on the intermediate layer.

2. The magnetic recording medium of claim 1, wherein the Pt of the seed layer is in a range of 30 atomic percent (at. %) to 70 at. %.

3. The magnetic recording medium of claim 2, wherein the Pt of the seed layer is about 60 at. % of Pt.

4. The magnetic recording medium of claim 1, wherein the seed layer consists of Ni-Pt, wherein the Pt is about 60 atomic percent.

5. The magnetic recording medium of claim 1, wherein the Ni-Pt of the seed layer forms a face-centered cubic (FCC) lattice.

6. The magnetic recording medium of claim 1, wherein a lattice constant of the Ni-Pt of the seed layer is in a range of 3.68 Angstroms to 3.85 Angstroms.

7. The magnetic recording medium of claim 1, wherein a lattice mismatch of the Ni-Pt of the seed layer to the intermediate layer is 5% or less.

8. The magnetic recording medium of claim 1, wherein a lattice mismatch of the Ni-Pt of the seed layer to the intermediate layer is 1% or less.

9. The magnetic recording medium of claim 1, wherein a lattice mismatch of the Ni-Pt of the seed layer to the intermediate layer is 0.4% or less.

10. The magnetic recording medium of claim 1, wherein the seed layer does not comprise an oxide.

11. The magnetic recording medium of claim 1, wherein the seed layer comprises a plurality of seed layers consisting of Ni-Pt, each seed layer having a different percentage of Pt in the Ni-Pt.

12. A data storage device, comprising: the magnetic recording medium of claim 1; and a recording head configured to write information to the magnetic recording medium.

13. A method for manufacturing a magnetic recording medium, comprising: providing a substrate; providing an amorphous soft magnetic underlayer (SUL) on the substrate; providing a seed layer on the SUL, the seed layer comprising Ni-Pt, wherein Pt atoms have substitutionally replaced at least some of Ni atoms within a Ni lattice structure of the Ni-Pt; providing an intermediate layer comprising Ru on the seed layer; and providing a magnetic recording layer (MRL) on the intermediate layer.

14. The method of claim 13, wherein the Ni-Pt of the seed layer comprises Pt in a range of 30 atomic percent (at. %) to 70 at. %. ​ ​ 15. The method of claim 14, wherein the Ni-Pt of the seed layer comprises about 60 at. %.

16. The method of claim 13, wherein a lattice constant of the Ni-Pt of the seed layer is in a range of 3.68 Angstroms to 3.85 Angstroms.

17. The method of claim 13, wherein a lattice mismatch of the Ni-Pt of the seed layer to the intermediate layer is 5% or less.

18. The method of claim 13, wherein a lattice mismatch of the Ni-Pt of the seed layer to the intermediate layer is 1% or less.

19. The method of claim 13, wherein a lattice mismatch of the Ni-Pt of the seed layer to the intermediate layer is 0.4% or less.

20. The method of claim 13, wherein the seed layer comprises a plurality of seed layers composed of Ni-Pt, each seed layer having a different percentage of Pt in the Ni-Pt.

21. A magnetic recording medium, comprising: a substrate; an amorphous soft magnetic underlayer (SUL) on the substrate; a seed layer on the SUL; an intermediate layer comprising Ru on the seed layer, wherein a lattice mismatch of the seed layer to the intermediate layer is 1% or less; and a magnetic recording layer (MRL) on the intermediate layer.

22. The magnetic recording medium of claim 21, wherein a lattice mismatch of the seed layer to the intermediate layer is 0.4% or less.

23. The magnetic recording medium of claim 21, wherein the seed layer does not comprise an oxide.

24. The magnetic recording medium of claim 21, wherein the seed layer comprises Ni-Pt, wherein Pt is in a range of 30 atomic percent (at. %) to 70 at. %.

25. The magnetic recording medium of claim 24, wherein the seed layer comprises Ni-Pt, wherein Pt comprises about 60 at. %.

26. The magnetic recording medium of claim 21, wherein the seed layer is composed of Ni-Pt, wherein the Pt is about 60 atomic percent.

27. A data storage device, comprising: the magnetic recording medium of claim 21; and a recording head configured to write information to the magnetic recording medium. ​ ​

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