Wd Media, LLC

Western Digital Technologies, Inc.

Tomoko Seki

Antony Ajan

Paul Christopher Dorsey

Hoan Cong Ho

Hua Yuan

B Ramamurthy Acharya

Alexander S Chernyshov

Bincheng Wang

Rui Zhang

Gerardo Bertero

Pierre-Olivier Jubert

David Treves

Kumar Srinivasan

Shahid Ali Pirzada

Jiaxing Liu

Debashish Tripathy

Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium that has a magnetic recording layer on a MgO—TiO (MTO) underlayer, where the MTO underlayer is formed using pulsed DC sputtering and has less than 50 mol % of TiO. By providing an MTO layer with less than 50 mol % of TIO, smaller grain sizes may be achieved in the magnetic recording layer, providing for higher areal densities. In some embodiments, a second MTO underlayer is provided, which is formed using non-pulsed DC sputtering and has 50 mol % of TiO. That is, a dual-layer MTO underlayer may be provided with, e.g., an MgO-30TiO layer atop an MgO-50TiO layer.

Magnetic recording medium with magnesium-titanium oxide (MTO) layer formed using pulsed direct current sputter deposition

Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium. The HAMR medium includes a substrate, a heat sink layer on the substrate, and a plurality of magnetic recording layers on the heat sink layer. The plurality of magnetic recording layers includes a first magnetic layer and a second magnetic layer disposed on the first magnetic layer. The second magnetic layer includes FePt—Ag—Cu—X, wherein X is a segregant comprising BN. The HAMR medium can use BN-based segregants to improve a thermal gradient of the HAMR medium for better areal density capability (ADC) and enable the use of a MgO underlayer with reduced thickness.

Media structure with selected segregants configured to improve heat-assisted magnetic recording

Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium that has a magnetic recording layer on a magnesium oxide-titanium oxide (MTO) underlayer, where the MTO underlayer includes an additive material that chemically bonds with titanium. In some examples, the additive material includes iron-oxide, iron, carbon, or various aluminum oxides. By providing the additive material to the MTO that chemically bonds with the titanium of the MTO, diffusion of titanium from the MTO underlayer into the magnetic recording layer is mitigated to provide an improved recording layer that achieves improved areal densities. In some embodiments, an additional magnesium oxide-nitrogen underlayer is also provided, which may include more of the additive material.

Magnetic recording medium with underlayer configured to reduce diffusion of titanium into a magnetic recording layer

A heat-assisted magnetic recording (HAMR) medium has a multilayered underlayer between the heat-sink layer and the recording layer. One embodiment of the underlayer is a multilayer of a thermal barrier layer consisting essentially of MgO and TiO, and a seed layer containing MgO and nitrogen (N) directly on the thermal barrier layer, with the recording layer on and in contact with the seed layer. The interface between the thermal barrier layer and the seed layer contains Ti and N, some of which may be present as TiN to act as a diffusion barrier to prevent diffusion of the Ti into the recording layer. The Ti-containing thermal barrier layer has a higher thermal resistivity than the conventional MgO thermal barrier/seed layer and thus allows for reduced laser power to the recording layer while still achieving a high thermal gradient at the recording layer.

Heat-assisted magnetic recording (HAMR) medium with multilayered underlayer for the recording layer

Magnetic media having dual phase MgO-X seed layers with both MgO grains and segregants are provided. One such magnetic medium includes a substrate, a heatsink layer on the substrate, a dual phase seed layer on the heatsink layer, where the dual phase seed layer comprises MgO and a segregant, where a concentration of the MgO is greater than 50 percent by volume in the dual phase seed layer, and a magnetic recording layer including FePt on the dual phase seed layer.

Dual phase MgO-X seed layers for heat assisted magnetic recording media

High thermal gradient heatsinks for heat assisted magnetic recording media are provided. One example magnetic recording medium for heat assisted magnetic recording includes a substrate, a first seed layer on the substrate, a heatsink layer on the first seed layer and including Ru having a crystal texture of (11.0), a second seed layer on the heatsink layer, and a magnetic recording layer on the second seed layer. Methods for manufacturing such magnetic recording media are also disclosed.

High thermal gradient heatsink for heat assisted magnetic recording media

Thermal barrier layers and seed layers for control of thermal and structural properties of heat assisted magnetic recording (HAMR) media are provided. One such HAMR medium includes a substrate, a heat sink layer on the substrate, a thermal barrier layer of SrTiOon the heat sink layer, an underlayer of MgO on the thermal barrier layer, and a magnetic recording layer on the underlayer. Another such HAMR medium includes a substrate, a heat sink layer on the substrate, a thermal barrier layer of an ABO3-type oxide on the heat sink layer, and a magnetic recording layer on the thermal barrier layer.

Thermal barrier layers and seed layers for control of thermal and structural properties of HAMR media

A heat-assisted magnetic recording (HAMR) media stack is provided in which Iridium (Ir)-based materials may be utilized as a secondary underlayer instead of a Magnesium Oxide (MgO) underlayer utilized in conventional media stacks. Such Ir-based materials may include, e.g., pure Ir, Ir-based alloys, Ir-based compounds, as well as a granular Ir layer with segregants. The use of Ir or Ir-based materials as an underlayer provide advantages over the use of MgO as an underlayer. For example, DC sputtering can be utilized to deposit the layers of the media stack, where the deposition rate of Ir is considerably higher than that of MgO resulting in higher manufacturing production yields. Further still, less particles are generated during Ir-based layer deposition processes, and Ir-based underlayer can act as a better heat sink. Further still, the morphology and structure of a recording layer deposited on an Ir-based layer can be better controlled.

Iridium underlayer for heat assisted magnetic recording media

A soft underlayer (SUL) and methods for making an SUL are provided, the SUL having characteristics that make it compatible with the high temperature requirements associated with heat-assisted magnetic recording (HAMR) media growth and writing, e.g., temperatures greater than 500&#xb0; C. The SUL may have a high crystallization temperature of greater than 450&#xb0; C. and a high Curie temperature greater than 300&#xb0; C., for example. Additionally, the SUL can maintain a saturation magnetization value greater than, e.g., 9 kGauss, at such high temperatures, thereby having the ability to remain amorphous at temperatures up to, e.g., 650&#xb0; C., and exhibiting a relatively flat integrated noise profile from approximately 300&#xb0; C. to 650&#xb0; C. Further still, a spacer layer material is chosen such that inter-diffusion does not occur at these high temperatures.

Soft underlayer for heat assisted magnetic recording media

A recording medium having improved signal-to-noise ratio (SNR) capabilities and head-disk interface characteristics includes an etched smoothened underlayer, over which the recording layer is grown. One mechanism for increasing the SNR is by growing more columnar magnetic grain structures within the recording layer, which is facilitated by a smoother underlayer template.

Smooth structures for heat-assisted magnetic recording media

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, AgBO, AgMoO, AgVO, BO, MoO, VO, and/or combinations thereof.

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

A method and system provide a magnetic recording media usable in a heat assisted magnetic recording (HAMR) disk drive. The magnetic recording media includes a magnetic recording layer, a crystalline underlayer, and a crystalline heat sink layer. The crystalline underlayer is between the crystalline heat sink layer and the magnetic recording layer. The magnetic recording layer stores magnetic data. The crystalline underlayer has a first crystal structure. The crystalline heat sink layer has a second crystal structure.

Magnetic media capable of improving magnetic properties and thermal management for heat-assisted magnetic recording

Aspects of the present invention are directed to heat assisted magnetic recording (HAMR) media with a CoCrPtB based capping layer design that is capable of reducing switching field distribution and boosting signal-to-noise ratio of HAMR media. In one embodiment of the invention, a recording medium for heat assisted magnetic recording (HAMR) includes a substrate, a magnetic recording layer on the substrate, and a capping layer on and directly in contact with the magnetic recording layer. The capping layer includes CoCrPtB.

Systems and methods for providing capping layers for heat assisted magnetic recording media

Systems and methods for providing thermal barrier bilayers for heat assisted magnetic recording (HAMR) media are provided. One such HAMR medium includes a substrate, a heat sink layer on the substrate, a thermal barrier bilayer on the heat sink layer, the bilayer comprising a first thermal barrier layer on the heat sink layer and an amorphous underlayer on the first thermal barrier layer, and a magnetic recording layer on the amorphous underlayer, wherein a thermal conductivity of the first thermal barrier layer is less than a thermal conductivity of the amorphous underlayer.

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Sunnyvale, CA, United States of America

Tomoko Seki