Abstract: A patterned perpendicular magnetic recording disk with discrete data islands of recording layer (RL) material includes a substrate, a patterned exchange bridge layer of magnetic material between the substrate and the islands, and an optional exchange-coupling control layer (CCL) between the exchange bridge layer and the islands. The exchange bridge layer has patterned pedestals below the islands. The exchange bridge layer controls exchange interactions between the RLs in adjacent islands to compensate the dipolar fields between islands, and the pedestals concentrate the flux from the write head. The disk may include a soft underlayer (SUL) of soft magnetically permeable material on the substrate and a nonmagnetic exchange break layer (EBL) on the SUL between the SUL and the exchange bridge layer. In a thermally-assisted recording (TAR) disk a heat sink layer may be located below the exchange bridge layer and the SUL may be optional.

Abstract: A silicon/gold (Si/Au) bilayer seed structure is located in a film stack between an amorphous or crystalline lower layer and an upper layer with a well-defined crystalline structure. The seed structure includes a Si layer on the generally flat surface of the lower layer and a Au layer on the Si layer. The Si/Au interface initiates the growth of the Au layer with a face-centered-cubic (fcc) crystalline structure with the (111) plane oriented in-plane. The upper layer grown on the Au layer has a fcc or hexagonal-close-packed (hcp) crystalline structure. If the upper layer is a fcc material its [111] direction is oriented substantially perpendicular to the (111) plane of the Au layer and if the upper layer is a hcp material, its c-axis is oriented substantially perpendicular to the (111) plane of the Au layer.

Abstract: A method for making a bit-patterned-media (BPM) magnetic recording disk includes depositing a FePt (or CoPt) alloy recording layer, and then depositing a sealing layer on the FePt layer before high-temperature annealing. The high-temperature annealing causes the FePt to become substantially chemically-ordered in the L10 phase. After annealing, the sealing layer is removed. The sealing layer prevents nanoclustering and agglomeration of the FePt material at the surface of the FePt layer and the sealing layer, which would result in undesirable high surface roughness of the FePt, making patterning of the FePt layer difficult. The FePt layer can be patterned into the discrete islands for the BPM disk either before deposition of the sealing layer or after deposition and removal of the sealing layer. After patterning and removal of the sealing layer, the disk protective overcoat is deposited over the discrete data islands.

Abstract: A method for making a bit-patterned-media (BPM) magnetic recording disk includes depositing a FePt (or CoPt) alloy recording layer, and then depositing a sealing layer on the FePt layer before high-temperature annealing. The high-temperature annealing causes the FePt to become substantially chemically-ordered in the L10 phase. After annealing, the sealing layer is removed. The sealing layer prevents nanoclustering and agglomeration of the FePt material at the surface of the FePt layer and the sealing layer, which would result in undesirable high surface roughness of the FePt, making patterning of the FePt layer difficult. The FePt layer can be patterned into the discrete islands for the BPM disk either before deposition of the sealing layer or after deposition and removal of the sealing layer. After patterning and removal of the sealing layer, the disk protective overcoat is deposited over the discrete data islands.

Abstract: A patterned perpendicular magnetic recording disk has a Co-alloy recording layer patterned into discrete data islands arranged in concentric tracks and exhibits a narrow switching field distribution (SFD). The disk includes a substrate, a NiTa alloy planarizing layer on the substrate, a nonmagnetic Ru-containing underlayer on the planarizing layer, an oxide-free Co alloy magnetic recording layer, and an ultrathin oxide film between the Ru-containing layer and the Co-alloy magnetic recording layer. The oxide film may be an oxide selected from a Ta-oxide, a Co-oxide and a Ti-oxide, and is ultrathin so that it may be considered a discontinuous film. The planarizing layer and ultrathin oxide film improve the growth homogeneity of the Co-alloy recording layer, so that the patterned disk with data islands shows significantly reduced SFD.

Abstract: A patterned perpendicular magnetic recording disk has a Co-alloy recording layer patterned into discrete data islands arranged in concentric tracks and exhibits a narrow switching field distribution (SFD). The disk includes a substrate, a NiTa alloy planarizing layer on the substrate, a nonmagnetic Ru-containing underlayer on the planarizing layer, an oxide-free Co alloy magnetic recording layer, and an ultrathin oxide film between the Ru-containing layer and the Co-alloy magnetic recording layer. The oxide film may be an oxide selected from a Ta-oxide, a Co-oxide and a Ti-oxide, and is ultrathin so that it may be considered a discontinuous film. The planarizing layer and ultrathin oxide film improve the growth homogeneity of the Co-alloy recording layer, so that the patterned disk with data islands shows significantly reduced SFD.

Abstract: A patterned perpendicular magnetic recording disk has a pre-patterned disk substrate with pillars and trenches arranged in data regions and servo regions. In the data regions, the height of the data pillars is equal to or greater than the spacing between the data pillars, while in the servo regions the height of the servo pillars is less than the spacing between the servo pillars. A magnetic recording material with perpendicular magnetic anisotropy is deposited over the entire disk substrate, which results in magnetic material on the tops of the data pillars and servo pillars and in the servo trenches. The material in the data trenches is either nonmagnetic or discontinuous. After the application of a high DC magnetic field in one perpendicular direction and a low DC magnetic field in the opposite direction, the resulting disk has patterned servo sectors with servo pillars all magnetized in the same perpendicular direction and servo trenches magnetized in the opposite perpendicular direction.

Abstract: A bit-patterned media (BPM) magnetic recording disk has discrete data islands with an exchange-coupled composite (ECC) recording layer (RL) formed of a high-anisotropy chemically-ordered FePt alloy lower layer, a lower-anisotropy Co/X laminate or multilayer (ML) upper layer with perpendicular magnetic anisotropy, wherein X is Pt, Pd or Ni, and an optional nonmagnetic separation layer or coupling layer (CL) between the FePt layer and the ML. The FePt alloy layer is sputter deposited onto a seed layer structure, like a CrRu/Pt bilayer, while the disk substrate is maintained at an elevated temperature to assure the high anisotropy field Hk is achieved. The high-temperature deposition together with the CrRu/Pt seed layer structure provide a very smooth surface for subsequent deposition of the ML (and optional CL). The separate Co/X ML has by itself a very narrow switching field distribution (SFD), so that the SFD of the ECC RL is much narrower than the SFD for the FePt layer alone.

Abstract: A bit patterned magnetic media design for reducing the amount of magnetic material located in the trenches between topographic features is disclosed. An intermediate non-magnetic layer is deposited on the topography prior to depositing the functional magnetic layer on the topographic substrate features. The non-magnetic layer increases the width of the land regions that will ultimately support the functional magnetic layer. The non-magnetic layer also reduces the amount of trench deposition that can occur in the subsequent deposition of the magnetic recording layer. By eliminating most of the magnetic trench material, the amount of magnetic flux and readback interference produced by the trench material is reduced to an acceptable level.

Abstract: Multiple anisotropy layered magnetic structures for controlling reversal mechanism and tightening of switching field distribution in bit patterned media are disclosed. The invention extends the exchange spring concept to more variable and sophisticated structures. Three or more layers with different anisotropy or anisotropy gradients increase writeability gains beyond the simple hard/soft bilayer exchange spring concept for BPM. The structures have a thin very hard, high anisotropy center layer that acts as a threshold or pinning layer for domain wall propagation through the entire media structure. In addition or alternatively, a thin very soft, low anisotropy center layer in between the commonly used soft surface layer and hard media layer allows quick initial propagation of the domain wall into the center of the media structure. Various properties of the media structures can be tuned more independently for optimization if using more advanced multi-anisotropy layer stacks.

Abstract: A patterned perpendicular magnetic recording disk with discrete data islands of recording layer (RL) material includes a substrate, a patterned exchange bridge layer of magnetic material between the substrate and the islands, and an optional exchange-coupling control layer (CCL) between the exchange bridge layer and the islands. The exchange bridge layer has patterned pedestals below the islands. The exchange bridge layer controls exchange interactions between the RLs in adjacent islands to compensate the dipolar fields between islands, and the pedestals concentrate the flux from the write head. The disk may include a soft underlayer (SUL) of soft magnetically permeable material on the substrate and a nonmagnetic exchange break layer (EBL) on the SUL between the SUL and the exchange bridge layer. In a thermally-assisted recording (TAR) disk a heat sink layer may be located below the exchange bridge layer and the SUL may be optional.

Abstract: A hard disk drive has a magnetic media disk comprising a substrate having an axis, and an exchange coupled, bit patterned media on the substrate arranged in a plurality of tracks. Each of the tracks has a pattern of islands extending in an axial direction from the disk. Each island comprises a first layer having a first anisotropy and a first layer radial width, and a second layer on the first layer and having a second anisotropy that is lower than the first anisotropy. The second layer radial width is less than the first layer radial width.

Abstract: A bit patterned magnetic media design for reducing the amount of magnetic material located in the trenches between topographic features is disclosed. An intermediate non-magnetic layer is deposited on the topography prior to depositing the functional magnetic layer on the topographic substrate features. The non-magnetic layer increases the width of the land regions that will ultimately support the functional magnetic layer. The non-magnetic layer also reduces the amount of trench deposition that can occur in the subsequent deposition of the magnetic recording layer. By eliminating most of the magnetic trench material, the amount of magnetic flux and readback interference produced by the trench material is reduced to an acceptable level.

Abstract: Multilayer magnetic structures control the switching field and tighten the switching field distribution in bit patterned media. A strain-inducing layer is excited, e.g., by a localized magnetic field or a localized thermal heating or a voltage, and induces a strain on the magnetic layer(s) of the patterned bit to initiate switching of the bit magnetization. The strain induced on the magnetic layer forces a rotation or an amplitude variation of the magnetic layer anisotropy. A localized magnetic field is simultaneously or subsequently applied to complete the switching of the bit magnetization. The invention provides control of switching field and switching field distribution for bit-patterned media devices.

Abstract: A silicon/gold (Si/Au) bilayer seed structure is located in a film stack between an amorphous or crystalline lower layer and an upper layer with a well-defined crystalline structure. The seed structure includes a Si layer on the generally flat surface of the lower layer and a Au layer on the Si layer. The Si/Au interface initiates the growth of the Au layer with a face-centered-cubic (fcc) crystalline structure with the (111) plane oriented in-plane. The upper layer grown on the Au layer has a fcc or hexagonal-close-packed (hcp) crystalline structure. If the upper layer is a fcc material its [111] direction is oriented substantially perpendicular to the (111) plane of the Au layer and if the upper layer is a hcp material, its c-axis is oriented substantially perpendicular to the (111) plane of the Au layer.

Abstract: A system according to one embodiment includes a magnetic recording medium having a magnetic layer with features in a discrete track configuration or a bit patterned configuration and an underlayer adjacent the magnetic layer, the underlayer comprising a material capable of forming surface plasmon resonance; and a magnetic head having: a writer for writing to the medium; and a near-field transducer for heating the medium for thermally assisted recording. Additional systems and methods are also presented.

Abstract: A patterned perpendicular magnetic recording medium has discrete magnetic islands, each of which has a recording layer (RL) structure that comprises two exchange-coupled ferromagnetic layers. The RL structure may be an “exchange-spring” RL structure with an upper ferromagnetic layer (MAG2), sometimes called the exchange-spring layer (ESL), ferromagnetically coupled to a lower ferromagnetic layer (MAG1), sometimes called the media layer (ML). The RL structure may also include a coupling layer (CL) between MAG1 and MAG2 that permits ferromagnetic coupling. The interlayer exchange coupling between MAG1 and MAG2 may be optimized, in part, by adjusting the materials and thickness of the CL. The RL structure may also include a ferromagnetic lateral coupling layer (LCL) that is in contact with at least one of MAG1 and MAG2 for mediating intergranular exchange coupling in the ferromagnetic layer or layers with which it is in contact (MAG2 or MAG1).

Abstract: A patterned perpendicular magnetic recording disk has a pre-patterned disk substrate with pillars and trenches arranged in data regions and servo regions. In the data regions, the height of the data pillars is equal to or greater than the spacing between the data pillars, while in the servo regions the height of the servo pillars is less than the spacing between the servo pillars. A magnetic recording material with perpendicular magnetic anisotropy is deposited over the entire disk substrate, which results in magnetic material on the tops of the data pillars and servo pillars and in the servo trenches. The material in the data trenches is either nonmagnetic or discontinuous. After the application of a high DC magnetic field in one perpendicular direction and a low DC magnetic field in the opposite direction, the resulting disk has patterned servo sectors with servo pillars all magnetized in the same perpendicular direction and servo trenches magnetized in the opposite perpendicular direction.

Abstract: A patterned perpendicular magnetic recording disk has a pre-patterned disk substrate with pillars and trenches arranged in data regions and servo regions. In the data regions, the height of the data pillars is equal to or greater than the spacing between the data pillars, while in the servo regions the height of the servo pillars is less than the spacing between the servo pillars. A magnetic recording material with perpendicular magnetic anisotropy is deposited over the entire disk substrate, which results in magnetic material on the tops of the data pillars and servo pillars and in the servo trenches. The material in the data trenches is either nonmagnetic or discontinuous. After the application of a high DC magnetic field in one perpendicular direction and a low DC magnetic field in the opposite direction, the resulting disk has patterned servo sectors with servo pillars all magnetized in the same perpendicular direction and servo trenches magnetized in the opposite perpendicular direction.

Abstract: A system according to one embodiment includes a magnetic recording medium having a magnetic layer with features in a discrete track configuration or a bit patterned configuration and an underlayer adjacent the magnetic layer, the underlayer comprising a material capable of forming surface plasmon resonance; and a magnetic head having: a writer for writing to the medium; and a near-field transducer for heating the medium for thermally assisted recording. Additional systems and methods are also presented.