Patent application number | Description | Published |
20080203053 | Method for manufacturing magnetic recording medium, stamper, transferring apparatus, and method for forming resin mask - A reliable magnetic recording medium manufacturing method is provided in which a resin material used for processing a recording layer into a concavo-convex pattern can be removed reliably. In the magnetic recording medium manufacturing method, an energy ray curable resin material is spread over a continuous recording layer. Then, a stamper having a predetermined concavo-convex pattern is brought into contact with the resin material to transfer the concavo-convex pattern to the resin material, and the resin material is irradiated with energy rays such that the irradiation energy on a portion excluding the edge portion of the resin material is greater than that on the edge portions. The curing reaction proceeds to a greater extent in the portion excluding the edge portions than in the edge portions. Then, the resin material is etched and removed such that more resin material is removed from the edge portions than from the other portion. | 08-28-2008 |
20080230960 | Method for manufacturing information recording medium, method for forming resin mask, transferring apparatus, and light-transmitting stamper - An information recording medium manufacturing method is provided in which a resin material can be reliably cured even when a light-transmitting stamper is used repeatedly. A resin mask forming method and a transferring apparatus and a light-transmitting stamper used in these methods are also provided. In the above methods, a visible light curable resin material is spread over a workpiece. Then, a light-transmitting stamper including a transferring portion having a predetermined concavo-convex pattern formed therein is brought into contact with the resin material to transfer the concavo-convex pattern to the resin material, and light including visible light is projected onto the resin material through the light-transmitting stamper to cure the resin material. | 09-25-2008 |
20080237938 | Method for manufacturing information recording medium, method of transferring concavo-convex pattern, and transfer apparatus - A method for manufacturing an information recording medium, a method of transferring a concavo-convex pattern, and a transfer apparatus are provided which are capable of curing a resin material with reliability even when using a light-transmitting stamper repeatedly. A stamper made of a light-transmitting resin, having a predetermined concavo-convex pattern formed on its transfer area, is inspected for an optical characteristic. The stamper is brought into contact with an energy-ray curable resin material applied to an object to be processed, thereby transferring the concavo-convex pattern to the resin material, and the resin material is irradiated with an energy ray through the stamper so that the resin material cures. The stamper is used a plurality of times to repeat these steps a plurality of times, thereby manufacturing a plurality of information recording media. | 10-02-2008 |
20090016205 | Optical Recording Medium and Method for Reproducing Information From Optical Recording Medium - An optical recording medium includes a substrate, a first dielectric layer, a recording layer, a second dielectric layer, a super-resolution layer, and a third dielectric layer, which are provided in that order. The super-resolution layer is formed of a material configured such that voids are generated when the material is irradiated with DC light at a predetermined irradiation power for 1 to 300 seconds. Therefore, super-resolution reproduction can be made such that the irradiation power of a readout laser beam does not depend on the size of a recording mark. | 01-15-2009 |
20090101624 | Method for manufacturing magnetic recording medium - A method for efficiently manufacturing a magnetic recording medium by filling concave portions of a concavo-convex patterned recording layer with a filler to provide sufficient surface flatness is provided. A cladding is etched by a dry etching method in which an etch rate of the cladding is equal to or higher than an etch rate of the filler. Then, by dry etching method in which an etch rate of the filler is higher than that of the cladding, the filler is etched so that a top surface of a diaphragm over a recording element (or a top surface of the recording element in absence of the diaphragm) is exposed, and the cladding remains over the concave portion of the concavo-convex pattern of the recording layer. | 04-23-2009 |
20090168244 | Magnetic recording medium, magnetic recording and reproducing apparatus, and method for manufacturing magnetic recording medium - The magnetic recording medium includes: a substrate; a recording layer formed in a predetermined concavo-convex pattern over the substrate, the concavo-convex pattern including a convex portion that serves as a recording element; and a filling portion that fills a concave portion between the recording elements. The filling portion comprises a metal-based main filling material and nitrogen. Nitrogen is unevenly distributed in the filling portion such that the ratio of the number of nitrogen atoms to the total number of atoms of the main filling material and nitrogen atoms is greater in the upper surface portion of the filling portion than in the lower portion thereof. | 07-02-2009 |
20090242508 | Method for manufacturing magnetic recording medium - A filling material different from a first mask layer (temporary coating material) is deposited over a workpiece to fill concave portions. At least part of excess portions of the filling material is removed by a dry etching method such that at least part of the side surfaces of the first mask layer over recording elements are exposed. Then, the first mask layer is removed by a dry etching method which uses a reactive gas having the property of chemically reacting with and removing both the filling material and the first mask layer as a processing gas and in which an etching rate for the first mask layer is higher than that for the filling material, and the etching rate for the filling material is higher than that for a recording layer (a lower layer that is in contact with a lower surface of the first mask layer over recording elements). | 10-01-2009 |
20090268595 | INFORMATION RECORDING MEDIUM AND RECORDING/REPRODUCING APPARATUS - On an information recording medium, a first region where first recording regions that are long in a radial direction are disposed at a predetermined pitch with first non-recording regions in between is provided in a preamble pattern region. A second recording region that connects first recording regions that are adjacent in a direction of rotation is provided in the first region. A second non-recording region that is longer in the direction of rotation than a length in the direction of rotation of the first non-recording regions at corresponding same-pattern-radius positions is provided at a position where a read of servo data is carried out following the first region. | 10-29-2009 |
20090310255 | Magnetic recording medium and magnetic recording and reproducing apparatus - A highly reliable magnetic recording medium is provided which has a recording layer formed in a concavo-convex pattern and wherein the recording layer is unlikely to cause a change in magnetic properties. The magnetic recording medium includes a substrate, a recording layer formed in a predetermined concavo-convex pattern over the substrate, convex portions of the concavo-convex pattern serving as recording elements; and a filler portion filling a concave portion between the recording elements. The filler portion comprises a metal-based main filler material and oxygen. Oxygen is unevenly distributed in the filler portion so that the ratio of the number of oxygen atoms to the total of the number of atoms of the main filler material and the number of oxygen atoms is greater in an upper surface portion of the filler portion than in a lower portion of the filler portion. | 12-17-2009 |
20100195237 | MAGNETIC RECORDING MEDIUM, RECORDING/REPRODUCING APPARATUS, AND STAMPER - A magnetic recording medium has data track patterns formed by concave/convex patterns in data recording regions on at least one surface of a substrate and servo patterns formed by concave/convex patterns in servo pattern regions between the data recording regions. The concave/convex patterns include convexes, at least protruding end portions of which are formed of magnetic material, and concaves. A burst pattern region of each servo pattern region includes N (where N is at least two) burst regions, in which burst patterns, where plural burst signal unitary parts are aligned along a direction of rotation, are formed as the servo patterns. The burst signal unitary parts formed in M (where M is no greater than (N−1)) out of the N burst regions are concaves, and the burst signal unitary parts formed in L (where L is equal to (N−M)) out of the N burst regions are convexes. | 08-05-2010 |
20100239888 | Magnetic recording medium and magnetic recording and reproducing apparatus - A magnetic recording medium is provided in which recording elements and concave portions have a clear difference in terms of magnetism at the boundaries therebetween, and which has favorable production efficiency. The magnetic recording medium includes a substrate; a recording layer formed in a predetermined concavo-convex pattern over the substrate, convex portions of the concavo-convex pattern serving as recording elements; and a filler portion filling a concave portion between the recording elements. A center part of a bottom surface of the concave portion protrudes from edge parts of the bottom surface of the concave portion in a direction away from the substrate. | 09-23-2010 |
20110024388 | METHOD FOR MANUFACTURING MAGNETIC RECORDING MEDIUM - A method for manufacturing a magnetic recording medium is provided which can sufficiently reduce variations in surface roughness even in the simultaneous presence of a region of a relatively wide concave and convex portion and a region of a relatively narrow concave and convex portion in the recording layer. The method includes the steps of etching a recording layer based on a (first) mask layer to process it in a concavo-convex pattern, and depositing a filler over the recording layer and the mask layer to fill a concave portion with the filler. In between those steps, provided is the step of removing part of the first mask layer over a recording element (a convex portion of the recording layer) by dry etching in which an etching rate for the mask layer is higher than that for the recording layer so that the mask layer remains over the recording element. | 02-03-2011 |
20110181984 | MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING AND REPRODUCING APPARATUS, AND METHOD FOR MANUFACTURING MAGNETIC RECORDING MEDIUM - The recording layer is made of both magnetic particles containing Co, Cr, and Pt and a nonmagnetic material containing Cr present among the magnetic particles. The recording element has an uneven Cr distribution such that the ratio of the number of Cr atoms that constitute the recording element to the total number of Co, Cr, and Pt atoms that constitute the recording element is less at the sidewall portion of the recording element than at the center portion of the recording element. The relationships given by Expressions (I) and (II) below are satisfied; | 07-28-2011 |