Seagate Technology Incorporated

Christopher Formato

Neil Deeman

Nobuo Kurataka

David S Kuo

Dieter Klaus Weller

Gennady G Gauzner

Hong Ying Wang

Lawrence Matthias Bryant

Sundeep Chauhan

Kim Yang Lee

Jing Gui

Koichi R Wago

David Shiao-Min Kuo

A method of fabricating a patterned magnetic recording medium, comprises steps of: (a) providing a layer stack including an uppermost non-magnetic interlayer; (b) forming a resist layer on the interlayer; (c) forming a first pattern comprising a first group of recesses extending through the resist layer and exposing a first group of spaced apart surface portions of the interlayer; (d) filling the first group of recesses with a layer of a hard mask material; (e) selectively removing the resist layer to form a second pattern comprising a second group of recesses extending through the hard mask layer and exposing a second group of spaced apart surface portions of the interlayer; and (f) filling the second group of recesses with a layer of a magnetically hard material forming a magnetic recording layer.

Process for fabricating patterned magnetic recording device

The invention relates to a method of manufacturing a patterned media Ni stamper comprising depositing a perfluorodecyltrichlorosilane release layer. The release layer eliminates bonding at the master-stamper interface. A permanent master for manufacturing a patterned media stamper is also provided.

Method of manufacturing a patterned media stamper

Process for fabricating patterned magnetic recording media

Embodiments of the invention generally provide an electron beam substrate processing system. In one embodiment, the present invention provides an electron beam substrate processing system where a spindle shaft used to rotate substrates during processing includes at least one optical encoder wheel assembly. The optical encoder wheel assembly is configured to provide rotational speed data signal to a rotational speed control system and a pattern generation clock circuit configured to a provide an angular pattern generator clock signal and to a pattern generator circuit. The pattern generation circuit is configured to control modulation of an electron beam used for substrate processing. In one aspect of the present invention, while the spindle shaft is rotated at a constant linear velocity, the pattern generation circuit controls the modulation of an electron beam such that written mark lengths are sized to be about constant in angular dimension.

Method and apparatus for constant linear velocity electron beam substrate processing

In a beam lithography operation the relative motion between a work piece and the exposure beam produces variations in linear speed at different regions of the work piece surface. For example, if a disk work piece rotates with a constant angular velocity (CAV) relative to the beam, the linear surface speed relative to the beam impact point increases in proportion to increasing radial distance of that point from the center of the disk. To provide uniform exposure dose, the duty cycle of pulses of the exposure beam are varied in accord with radial distance.

Exposure dose control of rotating electron beam recorder

The manufacture of magnetic disks for disk drives requires formation or servo tracks in a concentric pattern on the disk. Certain types of beam apparatuses for forming feature patterns on a disk shaped substrate, such as might be used in hard disk manufacture, however, provide spiral patterns. A ramp type deflection signal therefore is used to deflect the beam so as to form one circular pattern during each rotational cycle, and thereby convert the spiral pattern to a pattern comprising a series of circles.

Manufacture of concentric patterns from spiral source

A method of manufacturing a stamper/imprinter for use in patterning of a recording medium, comprising sequential steps of:

Utilizing permanent master for making stampers/imprinters for patterning of recording media

A method of manufacturing a stamper/imprinter for use in patterning of a recording medium comprising the sequential steps of providing a substrate/workpiece comprising a topographical pattern formed in a portion of a surface of the substrate/workpiece. The pattern defines a periphery. An alignment mark is formed in another portion of the surface of surrounding the periphery. An opaque protective film is formed overlying the entirety of the surface. A peripheral portion of the protective film is removed to expose the alignment mark. Selected portions of the substrate/workpiece are removed while the alignment mark is utilized for accurate alignment during the removal process. Remaining portions of the protective film are removed prior to use.

Method for protecting surface of stamper/imprinter during manufacture thereof

Embodiments of the invention generally provide an electron beam substrate processing system. In one embodiment, the present invention provides an electron beam substrate processing system where a spindle shaft used to rotate substrates during processing includes two encoder wheels. One encoder wheel is configured to provide a rotational speed data signal to a rotational speed control system. Another encoder wheel is configured to provide a pattern generator clock signal at a higher frequency than the rotational speed data signal to a pattern generator. In one embodiment of the present invention, at least one of the encoder wheels is positioned adjacent the substrate to minimize torsional and differential movements between the at least one encoder wheel and the substrate.

Method and apparatus for electron beam processing of substrates

A method of forming a topographical pattern in a surface of a resist layer, comprising sequential steps of:

Ultrasonic agitation-assisted development of resist layer of master stamper/imprinter

Embodiments of the invention generally provide an electron beam substrate processing system. In one embodiment, the present invention provides an electron beam substrate processing system where a spindle shaft used to rotate substrates during processing includes at least one optical encoder wheel assembly. The optical encoder wheel assembly is configured to provide rotational speed data signal to a rotational speed control system and a pattern generation clock circuit configured to a provide a corrected pattern generator clock signal to a pattern generator circuit. The pattern generation circuit is used to control modulation of an electron beam used for substrate processing. In one aspect of the present invention, repeatable deviations of the rotational speed are measured and processed during substrate processing to correct for such repeatable deviations to increase substrate pattern writing accuracy.

Method and apparatus for a formatter following electron beam substrate processing system

Hard disk servo data is recorded on a stamper master or a hard disk with a timing offset that converts the arc described by the servo data writer's rotary actuator into the arc described by the disk drive's rotary actuator.

Compensation for non-linearity in the servo writing process by program pattern delay

A stamper/imprinter for use in performing thermal imprint lithography of a substrate/workpiece surface to form a pattern of features in first portions of the surface intended to receive the pattern, without incurring random formation of undesired, disordered features in second portions of the substrate/workpiece surface not intended to receive the pattern, comprising an imprinting surface configured to substantially prevent formation of gaps between the imprinting surface and the second portions of the surface during stamping/imprinting. Embodiments include stampers/imprinters with a multilevel imprinting surface comprises a first portion having a first level for forming the pattern of features in the first portions of the surface and a second portion having a second level for substantially preventing formation of gaps between the imprinting surface and the second portions of the surface during stamping/imprinting.

Multi-level stamper for improved thermal imprint lithography

A dual-sided stamper/imprinter for simultaneously forming magnetic transition patterns in spaced-apart first and second layers of magnetic material by contact printing comprises a mechanically hard, substantially rigid magnetic material having high saturation magnetization and high permeability and including first and second oppositely facing imprinting surfaces, wherein each of the imprinting surfaced has a topographical pattern formed therein comprising a patterned plurality of spaced-apart recesses with a plurality of non-recessed areas therebetween, each topographical pattern corresponding to a magnetic transition pattern to be formed in a respective layer of magnetic material. Also disclosed is a method for manufacturing dual-sided stampers/imprinters.

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Brentwood, CA, United States of America

Christopher Formato