Patent application number | Description | Published |
20080212231 | Magnetic recording medium, magnetic recording and reproducing apparatus, and method for manufacturing magnetic recording medium - The magnetic recording medium includes a substrate and a recording layer formed in a predetermined concavo-convex pattern over the substrate, the recording layer including recording elements each formed as a convex portion of the recording layer. Surface steps are formed in an outer area including a radially outermost portion of a recording area. Each surface step is formed in such a manner that a portion over a concave portion between the recording elements is recessed toward the substrate to a level below a portion over the recording element. The surface steps are formed such that the recording area can be sectioned into an annular area adjoining the outer area and the outer area where height of the surface steps is larger than that in the annular area. | 09-04-2008 |
20090034115 | MAGNETIC RECORDING MEDIUM, RECORDING /REPRODUCING APPARATUS, AND STAMPER - A servo pattern is formed in a servo pattern region on at least one surface of a substrate of a magnetic recording medium by a concave/convex pattern including a plurality of convex parts, at least protruding end parts of which are formed of magnetic material, and at least one concave part. The servo pattern region includes an address pattern region and a burst pattern region. The at least one concave part is formed in the servo pattern region so that a larger of an inscribed circle with a largest diameter out of inscribed circles on protruding end surfaces of the convex parts formed in the address pattern region and an inscribed circle with a largest diameter out of inscribed circles on protruding end surfaces of the convex parts formed in the burst pattern region is an inscribed circle with a largest diameter out of inscribed circles on protruding end surfaces of the convex parts formed in the servo pattern region. | 02-05-2009 |
20090067092 | Magnetic recording medium, magnetic recording and reproducing apparatus, and method for manufacturing magnetic recording medium - The magnetic recording medium includes: a recording layer formed over a substrate in a predetermined concavo-convex pattern, convex portions of the concavo-convex pattern constituting recording elements; a filler underlayer film formed on the bottoms of concave portions of the concavo-convex pattern; and a DLC filler formed on the filler underlayer film in contact with the filler underlayer film so as to fill the concave portions. The filler underlayer film is made of a material selected from the group consisting of a Si-containing material, a Ge-containing material, and a carbide material containing one or more metal elements selected from Ti, Ta, Nb, Mo, Zr, Cr, W, V, and Hf. | 03-12-2009 |
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 |
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 |
20130222092 | THIN-FILM MAGNETIC OSCILLATION ELEMENT - A thin-film magnetic oscillation element includes a pinned magnetic layer, a free magnetic layer, a nonmagnetic spacer layer provided between the pinned magnetic layer and the free magnetic layer, and a pair of electrodes, in which the easy axis of magnetization of the pinned magnetic layer lies in an in-plane direction of the plane of the pinned magnetic layer, and the easy axis of magnetization of the free magnetic layer lies in a direction normal to the plane of the free magnetic layer. Preferably, the relationship between the saturation magnetization Ms and the magnetic anisotropy field Ha of the free magnetic layer satisfies | 08-29-2013 |
20140340183 | THIN FILM MAGNETIC ELEMENT - A magnetoresistive effect element includes a pair of first soft magnetic layers that are arranged opposite to each other so as to sandwich a magnetoresistive effect film; a second soft magnetic layer; and a coil that is windingly formed about the second soft magnetic layer. When a rear end region cross-sectional area of the first soft magnetic layers is defined as S1r and a tip end region cross-sectional area of the second soft magnetic layer is defined as S2f, S2f>S1r is established, and when a tip end width of the first soft magnetic layers is defined as W1f and a rear end width of the first soft magnetic layers is defined as W1r, W1r>W1f is established. | 11-20-2014 |
20150061393 | VARIABLE VOLTAGE CIRCUIT - In a variable voltage circuit | 03-05-2015 |