Abstract: A planarization process may planarize a media disk that has data trenches between data features and larger servo trenches between servo features. A filler material layer is deposited on the media disk and provides step coverage of the trenches. The filler material has data recesses over the data trenches and servo recesses over the servo trenches that must be removed to produce a planar media surface. A first planarization process is used to remove the data recesses and a second planarization process is used to remove the servo recesses.

Abstract: The embodiments disclose a method for encoder frequency-shift compensation, including, determining frequency values of an input encoder signal, analyzing an encoder index clock signal and the input encoder signal to determine values of frequency-shifts and compensating for the values of the frequency-shifts to generate a frequency-shift compensated clock.

Abstract: A method for nano-patterning includes imprinting features in a resist with an imprint mold to form one or more topographic surface patterns on the imprinted resist. A a block copolymer (“BCP”) material is deposited on the imprinted resist, wherein a molecular dimension L0 of the BCP material correlates by an integer multiple to a spacing dimension of the one or more topographic surface patterns on the imprinted resist. The deposited BCP is annealed and at least a portion of the annealed BCP is removed, forming a template having discrete domains.

Abstract: A planarization process may planarize a media disk that has data trenches between data features and larger servo trenches between servo features. A filler material layer is deposited on the media disk and provides step coverage of the trenches. The filler material has data recesses over the data trenches and servo recesses over the servo trenches that must be removed to produce a planar media surface. A first planarization process is used to remove the data recesses and a second planarization process is used to remove the servo recesses.

Abstract: Producing a servo pattern on a media involves rotating a master, and during a first revolution of the master, forming a first transition at a first radial position on the master, and forming a first transition at a second radial position. During a second revolution of the master, a second transition at the first radial position is formed, and a second transition at the second radial position is formed. By exposing individual servo burst transitions located at the first and second radial positions, in separate disk revolutions, only one of the magnetic transitions will inherit a particular deflection from a nominal radial position. If there are any mechanical disturbances, each magnetic transition will be randomly displaced from its nominal position, reducing the written-in run-out by ?n, where n is the number of magnetic transitions in a particular servo burst.

Abstract: A magnetic recording medium (10) has a substrate (12) and a perpendicular magnetic recording layer (30) formed over the substrate (12). The perpendicular magnetic recording layer (30) has a granular layer (20) in which a magnetic signal is recorded and a continuous film layer (24) magnetically coupled to the granular layer (20). The continuous film layer (24) has hard magnetic portions (204) formed in positions corresponding to the recording regions where magnetic signals are recorded in the granular layer (20) and magnetic shield portions (202) formed between the hard magnetic portions (204), each having a magnetization curve whose slope is larger than those of the hard magnetic portions in the region where the applied magnetic filed is zero when the magnetization curve is measured, and each having a residual magnetic polarization smaller than those in the hard magnetic portions.

Abstract: A method of performing writable optical recording of a medium to form multilevel oriented nano-structures therein, comprises steps of providing a disc-shaped, writable recording medium having a planar surface; and encoding data/information in the medium by forming a plurality of multilevel nano-structured pits in the surface by scanning with a focused spot of optical energy to form at least one data track therein, including scanning the optical spot in a cross-track direction while rotating the disc about a central axis.

Abstract: A method for manufacturing a magnetic recording medium for perpendicular magnetic recording includes the steps of forming a first magnetic layer which has magnetic crystal grains exhibiting perpendicular magnetic anisotropy and nonmagnetic substances for magnetically separating the magnetic crystal grains from each other at grain boundaries of the magnetic crystal grains, forming a second magnetic layer which has magnetic grains exchange-coupled to the magnetic crystal grains, a grain boundary width of the magnetic grains being smaller than a grain boundary width of the magnetic crystal grains, and forming separation regions which magnetically separate tracks from each other in regions between the tracks of the magnetic recording medium in at least the second magnetic layer. The separation regions are disposed substantially only in the second magnetic layer of the first magnetic layer and the second magnetic layer.

Abstract: A polarization detection system structured for optical read-out of disc-shaped optical data/information storage and retrieval media with surfaces comprised of pits or marks configured as multilevel oriented nano-structures (ONS) with varying pit or mark orientations and widths. The polarization detection system comprises: an optical beam source; a stage for mounting and rotating an optical disc medium about a central axis; at least one photodetector; a beam splitter positioned in an optical path between the source and stage, for directing an incident beam from the source onto an optical disc mounted on the stage and a return beam from the disc onto the photodetector; and an optical polarizer positioned in an optical path between the beam splitter and the at least one photodetector, for detection and analysis of changes in polarization of the return beam effected by variation of the orientation of the walls and/or widths of the pits or marks of the disc.

Abstract: A magnetic recording medium for perpendicular magnetic recording includes a substrate, a granular layer having magnetic crystal grains exhibiting perpendicular magnetic anisotropy and nonmagnetic substances for magnetically separating the magnetic crystal grains from each other at grain boundaries of the magnetic crystal grains, and a continuous film layer having magnetic grains to be exchange-coupled to the magnetic crystal grains, the grain boundary width of the magnetic grains being smaller than that of the magnetic crystal grains, wherein separation regions for magnetically separating tracks from each other are disposed in regions between the tracks of the magnetic recording medium in at least the continuous film layer.

Abstract: A method of performing writable optical recording of a medium to form multilevel oriented nano-structures therein, comprises steps of providing a disc-shaped, writable recording medium having a planar surface; and encoding data/information in the medium by forming a plurality of multilevel nano-structured pits in the surface by scanning with a focused spot of optical energy to form at least one data track therein, including scanning the optical spot in a cross-track direction while rotating the disc about a central axis.

Abstract: [PROBLEMS] To improve the track density by reducing the track edge noise and sharpening the boundaries of a recording magnetic field by blocking the recording magnetic field spreading outside the recording region in magnetic recording. [MEANS FOR SOLVING PROBLEMS] A magnetic recording medium (10) has a substrate (12) and a perpendicular magnetic recording layer (30) formed over the substrate (12). The perpendicular magnetic recording layer (30) has a granular layer (20) in which a magnetic signal is recorded and a continuous film layer (24) magnetically coupled to the granular layer (20).

Abstract: A rotary apertured interferometric lithography (RAIL) system that includes interferometric lithography tools, a mask with a slit preferably with an arc shape, and a rotating stage is disclosed. The RAIL system could create a servo pattern of a recording-head trajectory of a hard disk drive in a master for magnetic-contact printing. The master can could be used to form arrays of sub-micron sized magnetic elements on a magnetic disk media for high-density magnetic recording applications.

Abstract: A rotary apertured interferometric lithography (RAIL) system that includes interferometric lithography tools, a mask with a slit preferably with an arc shape, and a rotating stage is disclosed. The RAIL system could create a servo pattern of a recording-head trajectory of a hard disk drive in a master for magnetic-contact printing. The master can could be used to form arrays of sub-micron sized magnetic elements on a magnetic disk media for high-density magnetic recording applications.

Abstract: A method of performing imprint lithography of a surface substrate includes a stamper having a thin lubricant coating thereon to facilitate release of the stamper from the imprinted surface to reduce degradation of image replication. Embodiments of the invention include stampers suitable for use in patterning servo information on magnetic recording media having a lubricant coating of from about 1 nm to about 20 nm.

Abstract: A rotary apertured interferometric lithography (RAIL) system that includes interferometric lithography tools, a mask with a slit preferably with an arc shape, and a rotating stage is disclosed. The RAIL system could create a servo pattern of a recording-head trajectory of a hard disk drive in a master for magnetic-contact printing. The master can could be used to form arrays of sub-micron sized magnetic elements on a magnetic disk media for high-density magnetic recording applications.

Abstract: A method of fabricating a patterned magnetic layer comprises sequential steps of: (a) providing a workpiece comprising a non-magnetic substrate, a layer of magnetic material overlying a surface of the substrate, and a layer of a non-magnetic material overlying the layer of magnetic material; (b) forming a layer of a mask material on the layer of non-magnetic material; (c) forming a topographical pattern comprising a plurality of recesses in the layer of mask material; (d) selectively removing portions of the layer of non-magnetic material proximate lower portions of the recesses, thereby exposing selected portions of the layer of magnetic material; (e) treating the exposed portions of the layer of magnetic material with a liquid for reducing the magnetic properties thereof; and (f) removing the topographically patterned layer of mask material.

Abstract: A method of fabricating a master stamper/imprinter for manufacturing a patterned recording medium by nano-imprint lithography comprises steps of: (a) providing a substrate having a surface; (b) forming a layer of a hybrid resist material on the surface, the resist layer having an exposed upper surface; (c) subjecting selected areas of the exposed upper surface of the resist layer to an energy beam to form therein a latent image of a topographical pattern to be formed in the resist layer and having a correspondence to a pattern to be formed in a patterned recording medium; and (d) developing the latent image into the topographical pattern in the resist layer, wherein only those areas of the resist layer which have received an energy beam exposure dose between a positive-tone threshold dose D0p and a negative-tone threshold dose D0n are developed.

Abstract: A magnetic recording medium for perpendicular magnetic recording includes a substrate, a granular layer having magnetic crystal grains exhibiting perpendicular magnetic anisotropy and nonmagnetic substances for magnetically separating the magnetic crystal grains from each other at grain boundaries of the magnetic crystal grains, and a continuous film layer having magnetic grains to be exchange-coupled to the magnetic crystal grains, the grain boundary width of the magnetic grains being smaller than that of the magnetic crystal grains, wherein separation regions for magnetically separating tracks from each other are disposed in regions between the tracks of the magnetic recording medium in at least the continuous film layer.

Abstract: A method of fabricating a patterned perpendicular magnetic recording medium comprises steps of: (a) providing a layer stack including a magnetically soft underlayer (“SUL”) and an overlying non-magnetic interlayer; (b) forming a masking layer on the non-magnetic interlayer; (c) forming a resist layer on the masking layer; (d) forming a pattern of recesses extending through the resist layer and exposing spaced apart surface portions of the masking layer; (e) extending the pattern of recesses through the masking layer to expose spaced apart surface portions of the interlayer; and (f) at least partially filling the pattern of recesses with a magnetically hard material to form a perpendicular magnetic recording layer.