HAMR media structure with intermediate layer underlying a magnetic recording layer having multiple sublayers

Information

  • Patent Grant
  • 9406329
  • Patent Number
    9,406,329
  • Date Filed
    Monday, November 30, 2015
    9 years ago
  • Date Issued
    Tuesday, August 2, 2016
    8 years ago
Abstract
Segregants for magnetic recording layers and materials for intermediate layers underlying the magnetic recording layers are provided for improved heat assisted magnetic recording (HAMR) media. One such HAMR medium includes a substrate, a heat sink layer on the substrate, an underlayer on the heat sink layer, an intermediate layer of TiON, VON, CrON, TiOC, VOC, TiONC, and/or combinations thereof, on the underlayer, and a magnetic recording layer of FePt on the intermediate layer. The magnetic recording layer further includes three sublayers, each having a different segregant. The segregant of the first magnetic recording sublayer on the intermediate layer includes AgBN, AgCN, AgBNC, AgB2O3, AgMoO3, AgV2O5, B2O3, MoO3, V2O5, and/or combinations thereof.
Description
BACKGROUND

Energy/Heat Assisted Magnetic Recording (EAMR/HAMR) systems can potentially increase the areal density of information recorded magnetically on various media. For example, to achieve magnetic information storage levels beyond 1 terabit per inch squared, smaller grain size media may be required. Such designs can demand higher Ku materials for a magnetic recording layer to sustain thermal stability, such as L10 ordered FePt alloys.


The layer beneath the FePt magnetic recording layer (e.g., intermediate layer or underlayer) may be important to the media design to achieve the desired microstructure of the FePt magnetic recording layer. For example, one aspect controlling the FePt microstructure is the interfacial energy between the FePt magnetic recording layer and the intermediate layer, which varies depending on the segregant in the FePt magnetic recording layer and the intermediate layer properties. Recently, HAMR media including FePt magnetic recording layers has been optimized in terms of microstructure and magnetic properties using an MgO intermediate layer, together with a carbon segregant in the FePt magnetic recording layer.


However, when using intermediate layers other than MgO, carbon may not be an ideal segregant. For example, other intermediate layer materials may cause carbon to diffuse away from the intermediate layer interface, resulting in the formation of larger interconnected FePt grains. Accordingly, an improved HAMR media structure that addresses these shortcomings is needed.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is a top schematic view of a disk drive configured for heat assisted magnetic recording (HAMR) and including a magnetic medium with a FePt magnetic recording layer, intermediate layer and underlayer in accordance with one embodiment of the invention.



FIG. 2 is a side cross sectional schematic view of selected components of the HAMR system of FIG. 1 including the magnetic medium with the FePt magnetic recording layer, intermediate layer and underlayer in accordance with one embodiment of the invention.



FIG. 3 is side cross sectional view of a HAMR medium having a FePt magnetic recording layer, intermediate layer and underlayer in accordance with one embodiment of the invention.



FIG. 4 illustrates exemplary X-ray diffraction (XRD) patterns exemplifying perpendicular textures of FePt magnetic recording layers on TiON intermediate layers at different sputter oxygen percentages of the TiON intermediate layer in accordance with one embodiment of the invention.



FIG. 5A illustrates exemplary magnetic properties of HAMR media with an FePt—AgC magnetic recording layer on a TiON intermediate layer at different sputter oxygen percentages of the TiON intermediate layer in comparison with the magnetic property of an FePt—AgC magnetic recording layer on an MgO intermediate layer in accordance with one embodiment of the invention.



FIG. 5B illustrates exemplary magnetic properties of HAMR media with an FePt—AgBN magnetic recording layer on a TiON intermediate layer at different sputter oxygen percentages of the TiON intermediate layer in comparison with the magnetic property of an FePt—AgC magnetic recording layer on an MgO intermediate layer in accordance with one embodiment of the invention.



FIGS. 6A and 6B are plan transmission electron microscope (TEM) views of HAMR media with an FePt—AgBN magnetic recording layer on a TiON intermediate layer and an FePt—AgC magnetic recording layer on an MgO intermediate layer in accordance with one embodiment of the invention.



FIG. 7 is a flowchart of a process for manufacturing a HAMR medium including a FePt magnetic recording layer, an intermediate layer and an underlayer in accordance with one embodiment of the invention.





DETAILED DESCRIPTION

Referring now to the drawings, embodiments of heat assisted magnetic recording (HAMR) media that include a heat sink layer, an underlayer on the heat sink layer, an intermediate layer on the underlayer, and an FePt magnetic recording layer on the intermediate layer are illustrated. One such HAMR media design includes a FePt magnetic recording layer having a first FePt magnetic recording sublayer on the intermediate layer, a second FePt magnetic recording sublayer on the first FePt magnetic recording sublayer and a third FePt magnetic recording sublayer on the second FePt magnetic recording sublayer. Each of the FePt magnetic recording sublayers includes a different segregant. The segregant in the first FePt magnetic recording sublayer and the material used for the intermediate layer are selected to produce a substantially uniform distribution of segregant at the interface between the first FePt magnetic recording sublayer and the intermediate layer, thereby resulting in a substantially uniform FePt granular microstructure. In an aspect, an intermediate layer of TiON, VON, CrON, TiOC, VOC, TiONC, VONC, and/or combinations thereof, is utilized together with a segregant of AgBN, AgCN, AgBNC, AgB2O3, AgMoO3, AgV2O5, B2O3, MoO3, V2O5, and/or combinations thereof, in the first FePt magnetic recording sublayer.


The terms “above,” “over,” “on,” “below,” “under,” and “between” as used herein refer to a relative position of one layer with respect to other layers. As such, one layer deposited or disposed above, over, on, below, or under another layer may be directly in contact with the other layer or may have one or more intervening layers. Moreover, one layer deposited or disposed between layers may be directly in contact with the layers or may have one or more intervening layers.


It shall be appreciated by those skilled in the art in view of the present disclosure that although various exemplary fabrication methods are discussed herein with reference to magnetic recording disks, the methods, with or without some modifications, may be used for fabricating other types of recording disks, for example, optical recording disks such as a compact disc (CD) and a digital-versatile-disk (DVD), or magneto-optical recording disks, or ferroelectric data storage devices.



FIG. 1 is a top schematic view of a disk drive 100 configured for heat assisted magnetic recording (HAMR) and including a magnetic medium 102 with an FePt magnetic recording layer having multiple sublayers and intermediate layer underlying the FePt magnetic recording layer (not shown in FIG. 1, but see FIG. 3) in accordance with one embodiment of the invention. The laser (not visible in FIG. 1, but see FIG. 2) is positioned with a head/slider 108. Disk drive 100 may include one or more disks/media 102 to store data. Disk/media 102 resides on a spindle assembly 104 that is mounted to drive housing 106. Data may be stored along tracks in the magnetic recording layer of disk 102. The reading and writing of data is accomplished with the head 108 that may have both read and write elements. The write element is used to alter the properties of the magnetic recording layer of disk 102 and thereby write information thereto. In one embodiment, head 104 may have magneto-resistive (MR), or giant magneto-resistive (GMR) elements. In another embodiment, head 104 may be another type of head, for example, an inductive read/write head or a Hall Effect head.


In operation, a spindle motor (not shown) rotates the spindle assembly 104, and thereby rotates disk 102 to position head 108 at a particular location along a desired disk track. The position of head 104 relative to disk 102 may be controlled by position control circuitry 110.



FIG. 2 is a side cross sectional schematic view of selected components of the HAMR system of FIG. 1 including the magnetic medium 102 with the FePt magnetic recording layer having multiple sublayers and intermediate layer underlying the FePt magnetic recording layer (not shown in FIG. 2, but see FIG. 3) in accordance with one embodiment of the invention. The HAMR system components also include a sub-mount 112 attached to a top surface of the slider 108. A laser 114 is attached to the sub-mount 112, and possibly to the slider 108. The slider 108 includes the write element and the read element positioned along an air bearing surface (ABS) of the slider for writing information to, and reading information from, respectively, the media 102.


In operation, the laser 114 is configured to direct light energy to a waveguide in the slider 108 which directs the light to a near field transducer (NFT) near the air bearing surface (e.g., bottom surface) of the slider. Upon receiving the light from the laser via the waveguide, the NFT generates localized heat energy that heats a portion of the media 102 near the write element and the read element. FIGS. 1 and 2 illustrate a specific embodiment of a HAMR system. In other embodiments, the improved media with the FePt magnetic recording layer and intermediate layer can be used in other suitable HAMR systems.



FIG. 3 is side cross sectional view of a HAMR medium 200 having a magnetic recording layer 214 with multiple sublayers and an intermediate layer 212 underlying the magnetic recording layer 214 in accordance with one embodiment of the invention. The medium 200 has a stacked structure with a glass substrate 202 at a bottom/base layer, an adhesion layer 204 on the glass substrate 202, a seed layer 206 on the adhesion layer 204, a heat sink layer 208 on the seed layer 206, an underlayer 210 on the heat sink layer 208, the intermediate layer 212 on the underlayer 210, the magnetic recording layer 214 on the intermediate layer 212, and a carbon overcoat layer 222 on the magnetic recording layer 214. In some embodiments, the adhesion layer 204, seed layer 206, and carbon overcoat layer 222 can be omitted from the medium structure.


The magnetic recording layer 214 includes a first magnetic recording sublayer 216 on the intermediate layer 212, a second magnetic recording sublayer 218 on the first magnetic recording sublayer 216, and a third magnetic recording sublayer 220 on the second magnetic recording sublayer 218. Each of the magnetic recording sublayers 216, 218, and 220 is made of FePt. In an exemplary embodiment, each of the magnetic recording sublayers 216, 218, and 220 includes L10 phase FePt. Providing three sublayers in the FePt magnetic recording layer 214 enables growth of columnar and thick granular media, which results in low roughness, improved read-back signal and improved overall media performance.


Each of the magnetic recording sublayers 216, 218, and 220 includes one or more segregants. In one embodiment, the segregant included in each of the magnetic recording sublayers is different. The segregant in the first FePt magnetic recording sublayer 216 and the material used for the intermediate layer 212 are selected to produce a substantially uniform distribution of segregant at the interface between the first FePt magnetic recording sublayer 216 and the intermediate layer 212, thereby resulting in a substantially uniform FePt granular microstructure. In one instance, a substantially uniform FePt granular microstructure is produced when the FePt grain diameter is between about 7.5 nm and about 8.5 nm with a standard deviation of between about 2.5 nm and about 3.5 nm. In one embodiment, an intermediate layer 212 of TiON, VON, CrON, TiOC, VOC, TiONC, VONC, and/or combinations thereof, is utilized together with a segregant of AgBN, AgCN, AgBNC, AgB2O3, AgMoO3, AgV2O5, B2O3, MoO3, V2O5, and/or combinations thereof, in the first FePt magnetic recording sublayer 216. In other embodiments, the segregant in the first magnetic recording sublayer may include other oxide, nitride or carbide segregants that have a surface energy less than 0.1 Joules per meter squared (J/m2).


For example, in an exemplary embodiment, the intermediate layer 212 includes TiOxN(1-x), where x is between about 0.4 and about 0.5. In another exemplary embodiment, the segregant in the first magnetic recording sublayer 216 includes AgBN. In a further exemplary embodiment, the first magnetic recording sublayer 216 includes an AgBN segregant having a BN content in the AgBN segregant that may be between about 25 mole percent and about 40 mole percent. In still a further exemplary embodiment, the first magnetic recording sublayer 216 includes an AgBN segregant and the intermediate layer 212 includes TiON.


In one embodiment, the underlayer 210 can be made of one or more materials such as TiN, CrN, VN, TiC, VC, RuAl, RuTi, FeAl, SrTiO3, BaTiO3, BaSnO3, MgO, W, Mo, Cr, NiAl, combinations thereof, and/or other suitable materials known in the art. For example, in an exemplary embodiment, the underlayer 210 includes TiN and the intermediate layer includes TiON.


In several embodiments, the intermediate layer 212 operates as a thermal barrier layer. For example, the intermediate layer 212 may be configured to (e.g., the materials for the intermediate layer are selected to) facilitate a heat transfer from the magnetic recording layer 214 to the heat sink layer 208, and impede a heat transfer from the heat sink layer 208 to the magnetic recording layer 214.


In several embodiments, the thermal conductivity (κ) of the intermediate layer 212 is less than the thermal conductivity of the underlayer 210. For example, in embodiments in which the intermediate layer 212 includes TiOxN(1-x) (where x=0.4 to 0.5) and the underlayer 210 includes TiN, the thermal conductivity of TiOxN(1-x) is about 5 Watts per meter Kelvin (W/mK), whereas the thermal conductivity of TiN is about 10 W/mK. This can also be compared to the thermal conductivity of MgO, which is around 10 W/mK. Thus, utilizing an intermediate layer 212 of TiOxN(1-x) underneath the magnetic recording layer provides improved thermal conductivity properties of the HAMR medium 200 as compared to using MgO as the intermediate layer.


In addition, TiOxN(−x) may further provide improved optical properties over that provided by MgO. For example, the plasmonic effect observable in TiON may improve the optical impedance of the HAMR medium 200 during writing operations. Furthermore, the use of TiON may also result in similar or better magnetic performance in the magnetic recording layer(s) than the use of MgO.


In one embodiment, the segregant in the second magnetic recording sublayer 218 can be made of one or more materials such as BNC, BN, combinations thereof, and/or other suitable materials known in the art. In addition, the segregant in the third magnetic recording sublayer 220 can be made of one or more materials such as BNSiO2, BNZrO2, BNTa2O5, combinations thereof, and/or other suitable materials known in the art.


In one embodiment, the substrate 202 can be made of one or more materials such as an Al alloy, NiP plated Al, glass, glass ceramic, and/or combinations thereof. In one embodiment, the adhesion layer 204 can includes one or more materials such as CrTa, NiTa, combinations thereof, and/or other suitable materials known in the art.


In one embodiment, the seed layer 206 can be made of one or more materials such as RuAl, Cr, combinations thereof, and/or other suitable materials known in the art. In one embodiment, the heat sink layer 208 can be made of one or more materials such as W, Mo, Cr, Ru, Cu, Ag, Cu alloy, Ag alloy, combinations thereof, and/or other suitable materials known in the art.


In one embodiment, an intermediate layer 212 of TiON is deposited using a non-reactive sputtering process with a composite target of TiON. In another embodiment, an underlayer 210 of TiN and an intermediate layer 212 of TiON are sputter-deposited using a pure TiN target with a two-step process in one chamber. In the first step, the TiN underlayer 210 can be sputter-deposited first using pure Ar gas. Then, in the second step, the TiON intermediate layer 212 can be formed using a dc-reactive sputtering process in a mixture of Ar and O2 gas. In an aspect, the amount of oxygen in the TiON intermediate layer can be tuned by varying the ratio of the Ar/O2 flow rate to maximize the texture quality of the FePt magnetic recording layer. For example, the O2 content in the Ar/O2 mixture can vary between about 1.6 percent and about 1.8 percent, thus producing an intermediate layer of TiOxN(1-x), where x is between about 0.4 and about 0.5. In addition, as the oxygen percentage increases, the transmittance and reflectance of the TiON intermediate layer increases. Therefore, in embodiments in which higher transmittance and reflectance of the TiON intermediate layer are desired, the O2 content percentage can be greater than or equal to 1.8 percent. However, at O2 content percentages higher than 1.8 percent, the FePt texture quality may degrade.



FIG. 4 illustrates exemplary X-ray diffraction (XRD) patterns 300 exemplifying perpendicular textures of FePt magnetic recording layers on TiON intermediate layers at different sputter oxygen percentages of the TiON intermediate layer in accordance with one embodiment of the invention. Each XRD pattern 300 provides a measurement of the intensity over a range of angles (2θ) of the detector. A baseline XRD pattern 302 illustrates the intensity of a FePt—C magnetic recording layer over an MgO intermediate layer. Pronounced peaks of the FePt magnetic recording layer with (001) and (002) texture appear in the baseline XRD pattern 302, indicating a high quality FePt magnetic recording layer (good FePt microstructure/texture).


Each XRD pattern behind the baseline XRD pattern illustrates the intensity of a FePt—AgBN magnetic recording layer over a TiON intermediate layer at a particular sputter oxygen percentage of TiON. The O2 percentage utilized in the dc-reactive sputtering process of TiON increases from 0 percent in the first XRD pattern 304 behind the baseline XRD pattern 302 to 2.5 percent in the last XRD pattern 306. As can be seen in FIG. 4, XRD pattern 308, representing an O2 percentage between about 1.6 and 1.8, provides the best texture and is comparable to the texture achieved using MgO, as observed in the baseline XRD pattern 302. In addition to the FePt magnetic recording layer (001) and (002) peaks, the intermediate layer (TiON/MgO) and underlayer (RuAl) peaks can also be observed from FIG. 4.



FIG. 5A illustrates exemplary magnetic properties of HAMR media with an FePt—AgC magnetic recording layer on a TiON intermediate layer at different sputter oxygen percentages of the TiON intermediate layer (TiON UL) in comparison with the magnetic property of an FePt—AgC magnetic recording layer on an MgO intermediate layer (MgO—POR) in accordance with one embodiment of the invention. As can be seen in FIG. 5A, the coercivity (Hc) of an FePt—AgC magnetic recording layer on an MgO intermediate layer (MgO—POR) is about 40 kiloOersteds (kOe). By comparison, the coercivity of a FePt—AgC magnetic recording layer on a TiON intermediate layer (TiON UL) varies between about 10 kOe and 30 kOe, depending on the O2 content percentage used during dc-reactive sputtering of the TiON intermediate layer. The maximum coercivity of about 30 kOe occurs at an O2 sputter content of about 1.8 percent. Thus, the magnetic properties of a FePt magnetic recording layer including a carbon segregant are adversely affected when deposited over a TiON intermediate layer.



FIG. 5B illustrates exemplary magnetic properties of HAMR media with an FePt—AgBN magnetic recording layer on a TiON intermediate layer at different sputter oxygen percentages of the TiON intermediate layer (TiON UL) in comparison with the magnetic property of an FePt—AgC magnetic recording layer on an MgO intermediate layer (MgO—POR) in accordance with one embodiment of the invention. As can be seen in FIG. 5B, the coercivity of an FePt—AgBN magnetic recording layer on a TiON intermediate layer (TiON UL) varies between about 20 kOe and 40 kOe, depending on the O2 content percentage used during dc-reactive sputtering of the TiON intermediate layer. The maximum coercivity of about 40 kOe occurs at an O2 sputter content of about 1.6 percent. The maximum coercivity of the FePt—AgBN magnetic recording layer at about 1.6 percent O2 content of the TiON intermediate layer (TiON UL) is approximately equal that of the FePt—AgC magnetic recording layer on MgO (MgO—POR). Therefore, similar magnetic properties to that found in FePt—C magnetic recording layers deposited over an MgO intermediate layer can be achieved by using a BN segregant in the FePt magnetic recording layer deposited over a TiON intermediate layer.



FIGS. 6A and 6B are plan transmission electron microscope (TEM) views of HAMR media with an FePt—AgBN magnetic recording layer on a TiON intermediate layer and an FePt—AgC magnetic recording layer on an MgO intermediate layer in accordance with one embodiment of the invention. As can be seen by comparing FIGS. 6A and 6B, the microstructure of the FePt—AgBN magnetic recording layer deposited over a TiON intermediate layer is similar to the microstructure of the FePt—AgC magnetic recording layer deposited on an MgO intermediate layer.



FIG. 7 is a flowchart of a process 400 for manufacturing a HAMR medium including a FePt magnetic recording layer, an intermediate layer and an underlayer in accordance with one embodiment of the invention. In particular embodiments, the process 400 can be used to manufacture the HAMR magnetic media of FIG. 3, FIG. 2, or FIG. 1. The process first provides a substrate in block 402. The process then provides a heat sink layer on the substrate in block 404. The process then provides an underlayer on the heat sink layer in block 406. The process then provides an intermediate layer on the underlayer in block 408. The process then provides a magnetic recording layer including three magnetic recording sublayers on the intermediate layer in block 410.


In a number of embodiments, the process can manufacture the layers of the HAMR medium with any of the numerous variations described above for the embodiments of FIGS. 1, 2, and 3. For example, in one such case, the process can also provide an adhesion layer between the substrate and the heat sink layer, a seed layer between the adhesion layer and the heat sink layer, and a carbon overcoat layer on the magnetic recording layer.


In several embodiments, the layers can include the materials described above. For example, the process may provide the underlayer on the heat sink layer by depositing a layer of TiN, CrN, RuAl, SrTiO3, MgO, W, Mo, Cr, NiAl, and/or combinations thereof on the heat sink layer. In addition, the process may provide the intermediate layer on the underlayer by depositing a layer of TiON, VON, CrON, TiOC, VOC, TiONC, and/or combinations thereof on the underlayer.


In some embodiments, the process provides the underlayer on the heat sink layer by sputter-depositing the underlayer using a pure TiN target in pure Ar gas to produce a TiN underlayer. In some embodiments, the process provides the intermediate layer on the underlayer by dc-reactive sputtering the intermediate layer using a pure TiN target in mixed Ar/O2 gas to produce a TiON intermediate layer. For example, the O2 content percentage in the mixed Ar/O2 gas may be between about 1.6 and 1.8. In some embodiments, the process provides the intermediate layer on the underlayer by using a non-reactive sputtering process with a composite target of TiON.


In some embodiments, the process provides the magnetic recording layer by sputter-depositing the FePt—X granular magnetic recording sublayers onto the TiON/TiN layers. For example, the segregant used in the first magnetic recording sublayer may include AgBN, AgCN, AgBNC, AgB2O3, AgMoO3, AgV2O5, B2O3, MoO3, V2O5, and/or combinations thereof. As another example, the segregant used in the second magnetic recording sublayer may include BNC, BN, and/or combinations thereof. As yet another example, the segregant used in the third magnetic recording sublayer may include BNSiO2, BNZrO2, BNTa2O5, and/or combinations thereof.


In one embodiment, the process can perform the sequence of actions in a different order. In another embodiment, the process can skip one or more of the actions. In other embodiments, one or more of the actions are performed simultaneously. In some embodiments, additional actions can be performed.


While the above description contains many specific embodiments of the invention, these should not be construed as limitations on the scope of the invention, but rather as examples of specific embodiments thereof. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their equivalents.

Claims
  • 1. A medium for heat assisted magnetic recording, the medium comprising: a substrate;a heat sink layer on the substrate;an underlayer on the heat sink layer;an intermediate layer on the underlayer, the intermediate layer comprising a material selected from the group consisting of: TiON, VON, CrON, TiOC, VOC, TiONC, VONC, and combinations thereof; anda magnetic recording layer on the intermediate layer, the magnetic recording layer comprising: a first magnetic recording sublayer on the intermediate layer, the first magnetic recording sublayer comprising FePt with a first segregant, the first segregant comprising a material selected from the group consisting of: AgBN, AgCN, AgBNC, AgB2O3, AgMoO3, AgV2O5, B2O3, MoO3, V2O5, and combinations thereof,a second magnetic recording sublayer on the first magnetic recording sublayer, the second magnetic recording sublayer comprising FePt with a second segregant different than the first segregant, anda third magnetic recording sublayer on the second magnetic recording sublayer, the third magnetic recording sublayer comprising FePt with a third segregant different than the first segregant and the second segregant.
  • 2. The medium of claim 1, wherein the intermediate layer comprises TiOxN(1-x), where x is between about 0.4 and about 0.5.
  • 3. The medium of claim 1, wherein the underlayer comprises a material selected from the group consisting of: TiN, CrN, VN, TiC, VC, RuAl, RuTi, FeAl, SrTiO3, BaTiO3, BaSnO3, MgO, W, Mo, Cr, NiAl, and combinations thereof.
  • 4. The medium of claim 3, wherein the underlayer comprises TiN.
  • 5. The medium of claim 1, wherein the first segregant comprises AgBN.
  • 6. The medium of claim 5, wherein the first segregant comprises a BN content between about 25 mole percent and about 40 mole percent.
  • 7. The medium of claim 5, wherein the intermediate layer comprises TiON.
  • 8. The medium of claim 1, wherein the second segregant comprises a material selected from the group consisting of: BNC, BN, and combinations thereof.
  • 9. The medium of claim 1, wherein the third segregant comprises a material selected from the group consisting of: BNSiO2, BNZrO2, BNTa2O5, and combinations thereof.
  • 10. The medium of claim 1, wherein the heat sink layer comprises a material selected from the group consisting of: W, Mo, Ru, Cr, Cu, Ag, Cu alloy, Ag alloy, and combinations thereof.
  • 11. The medium of claim 1, further comprising: an adhesion layer on the substrate, the adhesion layer comprising a material selected from the group consisting of: CrTa, NiTa, and combinations thereof;a seed layer on the adhesion layer, the seed layer comprising a material selected from the group consisting of: RuAl, Cr, and combinations thereof;wherein the heat sink layer is on the seed layer.
  • 12. The medium of claim 1, wherein the intermediate layer is deposited using a reactive sputtering process in a mixture of Ar gas and O2 gas.
  • 13. The medium of claim 12, wherein the mixture of Ar gas and O2 gas comprises between about 1.6 percent O2 and about 1.8 percent O2.
  • 14. The medium of claim 1, wherein the intermediate layer is deposited using a non-reactive sputtering process with a composite target comprising TiON.
  • 15. A heat assisted magnetic recording system comprising: the medium of claim 1;a near-field transducer light source configured to direct light energy on to the medium; anda magnetic transducer configured to write information to the medium.
  • 16. A method for fabricating a medium for heat assisted magnetic recording, the method comprising: providing a substrate;providing a heat sink layer on the substrate;providing an underlayer on the heat sink layer;providing an intermediate layer on the underlayer, the intermediate layer comprising a material selected from the group consisting of: TiON, VON, CrON, TiOC, VOC, TiONC, VONC, and combinations thereof; andproviding a magnetic recording layer on the intermediate layer, the magnetic recording layer comprising: a first magnetic recording sublayer on the intermediate layer, the first magnetic recording sublayer comprising FePt with a first segregant, the first segregant comprising a material selected from the group consisting of: AgBN, AgCN, AgBNC, AgB2O5, AgMoO3, AgV2O5, B2O3, MoO3, V2O5, and combinations thereof,a second magnetic recording sublayer on the first magnetic recording sublayer, the second magnetic recording sublayer comprising FePt with a second segregant different than the first segregant, anda third magnetic recording sublayer on the second magnetic recording sublayer, the third magnetic recording sublayer comprising FePt with a third segregant different than the first segregant and the second segregant.
  • 17. The method of claim 16, wherein the intermediate layer comprises TiOxN(1-x), where x is between about 0.4 and about 0.5.
  • 18. The method of claim 16, wherein the underlayer comprises a material selected from the group consisting of: TiN, CrN, VN, TiC, VC, RuAl, RuTi, FeAl, SrTiO3, BaTiO3, BaSnO3, MgO, W, Mo, Cr, NiAl, and combinations thereof.
  • 19. The method of claim 16, wherein the underlayer comprises TiN.
  • 20. The method of claim 16, wherein the first segregant comprises AgBN.
  • 21. The method of claim 20, wherein the first segregant comprises a BN content between about 25 mole percent and about 40 mole percent.
  • 22. The method of claim 20, wherein the intermediate layer comprises TiON.
  • 23. The method of claim 16, wherein the second segregant comprises a material selected from the group consisting of: BNC, BN, and combinations thereof.
  • 24. The method of claim 16, wherein the third segregant comprises a material selected from the group consisting of: BNSiO2, BNZrO2, BNTa2O5, and combinations thereof.
  • 25. The method of claim 16, wherein the heat sink layer comprises a material selected from the group consisting of: W, Mo, Ru, Cr, Cu, Ag, Cu alloy, Ag alloy, and combinations thereof.
  • 26. The method of claim 16, further comprising: providing an adhesion layer on the substrate, the adhesion layer comprising a material selected from the group consisting of: CrTa, NiTa, and combinations thereof;providing a seed layer on the adhesion layer, the seed layer comprising a material selected from the group consisting of RuAl, Cr, and combinations thereof;wherein the heat sink layer is on the seed layer.
  • 27. The method of claim 16, wherein providing the underlayer on the heat sink layer comprises: depositing the underlayer using a sputtering process in substantially pure Ar gas.
  • 28. The method of claim 27, wherein providing the intermediate layer comprises: depositing the intermediate layer on the underlayer using a reactive sputtering process in a mixture of Ar gas and O2 gas.
  • 29. The method of claim 28: wherein the underlayer comprises TiN; andwherein the intermediate layer comprises TiOxN(1-x), where x is between about 0.4 and about 0.5.
  • 30. The method of claim 28, wherein the mixture of Ar gas and O2 gas comprises between about 1.6 percent O2 and about 1.8 percent O2.
  • 31. The method of claim 16, wherein providing the intermediate layer comprises: depositing the intermediate layer using a non-reactive sputtering process with a composite target comprising TiON.
US Referenced Citations (335)
Number Name Date Kind
6013161 Chen et al. Jan 2000 A
6063248 Bourez et al. May 2000 A
6068891 O'Dell et al. May 2000 A
6086730 Liu et al. Jul 2000 A
6099981 Nishimori Aug 2000 A
6103404 Ross et al. Aug 2000 A
6117499 Wong et al. Sep 2000 A
6136403 Prabhakara et al. Oct 2000 A
6143375 Ross et al. Nov 2000 A
6145849 Bae et al. Nov 2000 A
6146737 Malhotra et al. Nov 2000 A
6149696 Jia Nov 2000 A
6150015 Bertero et al. Nov 2000 A
6156404 Ross et al. Dec 2000 A
6159076 Sun et al. Dec 2000 A
6164118 Suzuki et al. Dec 2000 A
6200441 Gomicki et al. Mar 2001 B1
6204995 Hokkyo et al. Mar 2001 B1
6206765 Sanders et al. Mar 2001 B1
6210819 Lal et al. Apr 2001 B1
6216709 Fung et al. Apr 2001 B1
6221119 Homola Apr 2001 B1
6248395 Homola et al. Jun 2001 B1
6261681 Suekane et al. Jul 2001 B1
6270885 Hokkyo et al. Aug 2001 B1
6274063 Li et al. Aug 2001 B1
6283838 Blake et al. Sep 2001 B1
6287429 Moroishi et al. Sep 2001 B1
6290573 Suzuki Sep 2001 B1
6299947 Suzuki et al. Oct 2001 B1
6303217 Malhotra et al. Oct 2001 B1
6309765 Suekane et al. Oct 2001 B1
6358636 Yang et al. Mar 2002 B1
6362452 Suzuki et al. Mar 2002 B1
6363599 Bajorek Apr 2002 B1
6365012 Sato et al. Apr 2002 B1
6381090 Suzuki et al. Apr 2002 B1
6381092 Suzuki Apr 2002 B1
6387483 Hokkyo et al. May 2002 B1
6391213 Homola May 2002 B1
6395349 Salamon May 2002 B1
6403919 Salamon Jun 2002 B1
6408677 Suzuki Jun 2002 B1
6426157 Hokkyo et al. Jul 2002 B1
6429984 Alex Aug 2002 B1
6482330 Bajorek Nov 2002 B1
6482505 Bertero et al. Nov 2002 B1
6500567 Bertero et al. Dec 2002 B1
6528124 Nguyen Mar 2003 B1
6548821 Treves et al. Apr 2003 B1
6552871 Suzuki et al. Apr 2003 B2
6565719 Lairson et al. May 2003 B1
6566674 Treves et al. May 2003 B1
6571806 Rosano et al. Jun 2003 B2
6620531 Cheng Sep 2003 B1
6628466 Alex Sep 2003 B2
6664503 Hsieh et al. Dec 2003 B1
6670055 Tomiyasu et al. Dec 2003 B2
6682807 Lairson et al. Jan 2004 B2
6683754 Suzuki et al. Jan 2004 B2
6730420 Bertero et al. May 2004 B1
6743528 Suekane et al. Jun 2004 B2
6759138 Tomiyasu et al. Jul 2004 B2
6778353 Harper Aug 2004 B1
6795274 Hsieh et al. Sep 2004 B1
6855232 Jairson et al. Feb 2005 B2
6857937 Bajorek Feb 2005 B2
6893748 Bertero et al. May 2005 B2
6899959 Bertero et al. May 2005 B2
6916558 Umezawa et al. Jul 2005 B2
6939120 Harper Sep 2005 B1
6946191 Morikawa et al. Sep 2005 B2
6967798 Homola et al. Nov 2005 B2
6972135 Homola Dec 2005 B2
7004827 Suzuki et al. Feb 2006 B1
7006323 Suzuki Feb 2006 B1
7016154 Nishihira Mar 2006 B2
7019924 McNeil et al. Mar 2006 B2
7045215 Shimokawa May 2006 B2
7070870 Bertero et al. Jul 2006 B2
7090934 Hokkyo et al. Aug 2006 B2
7099112 Harper Aug 2006 B1
7105241 Shimokawa et al. Sep 2006 B2
7119990 Bajorek et al. Oct 2006 B2
7147790 Wachenschwanz et al. Dec 2006 B2
7161753 Wachenschwanz et al. Jan 2007 B2
7166319 Ishiyama Jan 2007 B2
7166374 Suekane et al. Jan 2007 B2
7169487 Kawai et al. Jan 2007 B2
7174775 Ishiyama Feb 2007 B2
7179549 Malhotra et al. Feb 2007 B2
7184139 Treves et al. Feb 2007 B2
7196860 Alex Mar 2007 B2
7199977 Suzuki et al. Apr 2007 B2
7208236 Morikawa et al. Apr 2007 B2
7220500 Tomiyasu et al. May 2007 B1
7229266 Harper Jun 2007 B2
7239970 Treves et al. Jul 2007 B2
7252897 Shimokawa et al. Aug 2007 B2
7277254 Shimokawa et al. Oct 2007 B2
7281920 Homola et al. Oct 2007 B2
7292329 Treves et al. Nov 2007 B2
7301726 Suzuki Nov 2007 B1
7302148 Treves et al. Nov 2007 B2
7305119 Treves et al. Dec 2007 B2
7314404 Singh et al. Jan 2008 B2
7320584 Harper et al. Jan 2008 B1
7329114 Harper et al. Feb 2008 B2
7375362 Treves et al. May 2008 B2
7420886 Tomiyasu et al. Sep 2008 B2
7425719 Treves et al. Sep 2008 B2
7471484 Wachenschwanz et al. Dec 2008 B2
7498062 Calcaterra et al. Mar 2009 B2
7531485 Hara et al. May 2009 B2
7537846 Ishiyama et al. May 2009 B2
7549209 Wachenschwanz et al. Jun 2009 B2
7569490 Staud Aug 2009 B2
7597792 Homola et al. Oct 2009 B2
7597973 Ishiyama Oct 2009 B2
7608193 Wachenschwanz et al. Oct 2009 B2
7632087 Homola Dec 2009 B2
7656615 Wachenschwanz et al. Feb 2010 B2
7682546 Harper Mar 2010 B2
7684152 Suzuki et al. Mar 2010 B2
7686606 Harper et al. Mar 2010 B2
7686991 Harper Mar 2010 B2
7695833 Ishiyama Apr 2010 B2
7722968 Ishiyama May 2010 B2
7733605 Suzuki et al. Jun 2010 B2
7736768 Ishiyama Jun 2010 B2
7755861 Li et al. Jul 2010 B1
7758732 Calcaterra et al. Jul 2010 B1
7833639 Sonobe et al. Nov 2010 B2
7833641 Tomiyasu et al. Nov 2010 B2
7910159 Jung Mar 2011 B2
7911736 Bajorek Mar 2011 B2
7924519 Lambert Apr 2011 B2
7944165 O'Dell May 2011 B1
7944643 Jiang et al. May 2011 B1
7955723 Umezawa et al. Jun 2011 B2
7983003 Sonobe et al. Jul 2011 B2
7993497 Moroishi et al. Aug 2011 B2
7993765 Kim et al. Aug 2011 B2
7998912 Chen et al. Aug 2011 B2
8002901 Chen et al. Aug 2011 B1
8003237 Sonobe et al. Aug 2011 B2
8012920 Shimokawa Sep 2011 B2
8038863 Homola Oct 2011 B2
8057926 Ayama et al. Nov 2011 B2
8062778 Suzuki et al. Nov 2011 B2
8064156 Suzuki et al. Nov 2011 B1
8076013 Sonobe et al. Dec 2011 B2
8092931 Ishiyama et al. Jan 2012 B2
8100685 Harper et al. Jan 2012 B1
8101054 Chen et al. Jan 2012 B2
8125723 Nichols et al. Feb 2012 B1
8125724 Nichols et al. Feb 2012 B1
8137517 Bourez Mar 2012 B1
8142916 Umezawa et al. Mar 2012 B2
8163093 Chen et al. Apr 2012 B1
8171949 Lund et al. May 2012 B1
8173282 Sun et al. May 2012 B1
8178480 Hamakubo et al. May 2012 B2
8206789 Suzuki Jun 2012 B2
8218260 Iamratanakul et al. Jul 2012 B2
8247095 Champion et al. Aug 2012 B2
8257783 Suzuki et al. Sep 2012 B2
8298609 Liew et al. Oct 2012 B1
8298689 Sonobe et al. Oct 2012 B2
8309239 Umezawa et al. Nov 2012 B2
8316668 Chan et al. Nov 2012 B1
8331056 O'Dell Dec 2012 B2
8354618 Chen et al. Jan 2013 B1
8367228 Sonobe et al. Feb 2013 B2
8383209 Ayama Feb 2013 B2
8394243 Jung et al. Mar 2013 B1
8397751 Chan et al. Mar 2013 B1
8399809 Bourez Mar 2013 B1
8402638 Treves et al. Mar 2013 B1
8404056 Chen et al. Mar 2013 B1
8404369 Ruffini et al. Mar 2013 B2
8404370 Sato et al. Mar 2013 B2
8406918 Tan et al. Mar 2013 B2
8414966 Yasumori et al. Apr 2013 B2
8425975 Ishiyama Apr 2013 B2
8431257 Kim et al. Apr 2013 B2
8431258 Onoue et al. Apr 2013 B2
8453315 Kajiwara et al. Jun 2013 B2
8488276 Jung et al. Jul 2013 B1
8491800 Dorsey Jul 2013 B1
8492009 Homola et al. Jul 2013 B1
8492011 Itoh et al. Jul 2013 B2
8496466 Treves et al. Jul 2013 B1
8517364 Crumley et al. Aug 2013 B1
8517657 Chen et al. Aug 2013 B2
8524052 Tan et al. Sep 2013 B1
8530065 Chernyshov et al. Sep 2013 B1
8546000 Umezawa Oct 2013 B2
8551253 Na'im et al. Oct 2013 B2
8551627 Shimada et al. Oct 2013 B2
8556566 Suzuki et al. Oct 2013 B1
8559131 Masuda et al. Oct 2013 B2
8562748 Chen et al. Oct 2013 B1
8565050 Bertero et al. Oct 2013 B1
8570844 Yuan et al. Oct 2013 B1
8580410 Onoue Nov 2013 B2
8584687 Chen et al. Nov 2013 B1
8591709 Lim et al. Nov 2013 B1
8592061 Onoue et al. Nov 2013 B2
8596287 Chen et al. Dec 2013 B1
8597723 Jung et al. Dec 2013 B1
8603649 Onoue Dec 2013 B2
8603650 Sonobe et al. Dec 2013 B2
8605388 Yasumori et al. Dec 2013 B2
8605555 Chernyshov et al. Dec 2013 B1
8608147 Yap et al. Dec 2013 B1
8609263 Chernyshov et al. Dec 2013 B1
8619381 Moser et al. Dec 2013 B2
8623528 Umezawa et al. Jan 2014 B2
8623529 Suzuki Jan 2014 B2
8623670 Mosendz Jan 2014 B1
8634155 Yasumori et al. Jan 2014 B2
8658003 Bourez Feb 2014 B1
8658292 Mallary et al. Feb 2014 B1
8665541 Saito Mar 2014 B2
8668953 Buechel-Rimmel Mar 2014 B1
8674327 Poon et al. Mar 2014 B1
8685214 Moh et al. Apr 2014 B1
8696404 Sun et al. Apr 2014 B2
8711499 Desai et al. Apr 2014 B1
8743666 Bertero et al. Jun 2014 B1
8758912 Srinivasan et al. Jun 2014 B2
8787124 Chernyshov et al. Jul 2014 B1
8787130 Yuan et al. Jul 2014 B1
8791391 Bourez Jul 2014 B2
8795765 Koike et al. Aug 2014 B2
8795790 Sonobe et al. Aug 2014 B2
8795857 Ayama et al. Aug 2014 B2
8800322 Chan et al. Aug 2014 B1
8811129 Yuan et al. Aug 2014 B1
8817410 Moser et al. Aug 2014 B1
8941950 Yuan et al. Jan 2015 B2
9076476 Kryder et al. Jul 2015 B2
9269480 Ajan Feb 2016 B1
20020060883 Suzuki May 2002 A1
20030022024 Wachenschwanz Jan 2003 A1
20040022387 Weikle Feb 2004 A1
20040132301 Harper et al. Jul 2004 A1
20040202793 Harper et al. Oct 2004 A1
20040202865 Homola et al. Oct 2004 A1
20040209123 Bajorek et al. Oct 2004 A1
20040209470 Bajorek Oct 2004 A1
20050036223 Wachenschwanz et al. Feb 2005 A1
20050142990 Homola Jun 2005 A1
20050150862 Harper et al. Jul 2005 A1
20050151282 Harper et al. Jul 2005 A1
20050151283 Bajorek et al. Jul 2005 A1
20050151300 Harper et al. Jul 2005 A1
20050155554 Saito Jul 2005 A1
20050167867 Bajorek et al. Aug 2005 A1
20050263401 Olsen et al. Dec 2005 A1
20060147758 Jung et al. Jul 2006 A1
20060181697 Treves et al. Aug 2006 A1
20060207890 Staud Sep 2006 A1
20070070549 Suzuki et al. Mar 2007 A1
20070245909 Homola Oct 2007 A1
20080075845 Sonobe et al. Mar 2008 A1
20080093760 Harper et al. Apr 2008 A1
20090117408 Umezawa et al. May 2009 A1
20090136784 Suzuki et al. May 2009 A1
20090169922 Ishiyama Jul 2009 A1
20090191331 Umezawa et al. Jul 2009 A1
20090202866 Kim et al. Aug 2009 A1
20090311557 Onoue et al. Dec 2009 A1
20100143752 Ishibashi et al. Jun 2010 A1
20100190035 Sonobe et al. Jul 2010 A1
20100196619 Ishiyama Aug 2010 A1
20100196740 Ayama et al. Aug 2010 A1
20100209601 Shimokawa et al. Aug 2010 A1
20100215992 Horikawa et al. Aug 2010 A1
20100232065 Suzuki et al. Sep 2010 A1
20100247965 Onoue Sep 2010 A1
20100261039 Itoh et al. Oct 2010 A1
20100279151 Sakamoto et al. Nov 2010 A1
20100300884 Homola et al. Dec 2010 A1
20100304186 Shimokawa Dec 2010 A1
20110038079 Choe Feb 2011 A1
20110097603 Onoue Apr 2011 A1
20110097604 Onoue Apr 2011 A1
20110171495 Tachibana et al. Jul 2011 A1
20110206947 Tachibana et al. Aug 2011 A1
20110212346 Onoue et al. Sep 2011 A1
20110223446 Onoue et al. Sep 2011 A1
20110244119 Umezawa et al. Oct 2011 A1
20110299194 Aniya et al. Dec 2011 A1
20110311841 Saito et al. Dec 2011 A1
20120069466 Okamoto et al. Mar 2012 A1
20120070692 Sato et al. Mar 2012 A1
20120077060 Ozawa Mar 2012 A1
20120127599 Shimokawa et al. May 2012 A1
20120127601 Suzuki et al. May 2012 A1
20120129009 Sato et al. May 2012 A1
20120140359 Tachibana Jun 2012 A1
20120141833 Umezawa et al. Jun 2012 A1
20120141835 Sakamoto Jun 2012 A1
20120148875 Hamakubo et al. Jun 2012 A1
20120156523 Seki et al. Jun 2012 A1
20120164488 Shin et al. Jun 2012 A1
20120170152 Sonobe et al. Jul 2012 A1
20120171369 Koike et al. Jul 2012 A1
20120175243 Fukuura et al. Jul 2012 A1
20120189872 Umezawa et al. Jul 2012 A1
20120196049 Azuma et al. Aug 2012 A1
20120207919 Sakamoto et al. Aug 2012 A1
20120214021 Sayama et al. Aug 2012 A1
20120225217 Itoh et al. Sep 2012 A1
20120251842 Yuan et al. Oct 2012 A1
20120251846 Desai et al. Oct 2012 A1
20120276417 Shimokawa et al. Nov 2012 A1
20120308722 Suzuki et al. Dec 2012 A1
20130040167 Alagarsamy et al. Feb 2013 A1
20130071694 Srinivasan et al. Mar 2013 A1
20130165029 Sun et al. Jun 2013 A1
20130175252 Bourez Jul 2013 A1
20130216865 Yasumori et al. Aug 2013 A1
20130230647 Onoue et al. Sep 2013 A1
20130314815 Yuan et al. Nov 2013 A1
20140011054 Suzuki Jan 2014 A1
20140044992 Onoue Feb 2014 A1
20140050843 Yi et al. Feb 2014 A1
20140093748 Chen Apr 2014 A1
20140151360 Gregory et al. Jun 2014 A1
20140234666 Knigge et al. Aug 2014 A1
20150138939 Hellwig May 2015 A1
20150194175 Chen Jul 2015 A1
Non-Patent Literature Citations (1)
Entry
Kumar Srinivasan , et al., U.S. Appl. No. 14/556,993, filed Dec. 1, 2014, 33 pages.