Tdk Corporation

Takahiro Suwa

Kazuhiro Hattori

Shuichi Okawa

Mitsuru Takai

Kazuya Shimakawa

Yoshikazu Soeno

Mikiharu Hibi

Katsuyuki Nakada

Kuniyasu Ito

Masato Takahashi

Narutoshi Fukuzawa

Yuji Kakinuma

Tetsuya Shibata

Katsumichi Tagami

Makoto Moriya

Takumi Aoki

Yoshinori Uchiyama

A magnetic element including a magnetoresistive effect film (MEF). Magnetic element includes an MEF and nonmagnetic spacer layer, first and second ferromagnetic layers, wherein layers being disposed with nonmagnetic spacer layer interposed therebetween, pair of electrodes disposed with MEF interposed therebetween in stacking direction of MEF at least two first soft magnetic layers, coil, and second soft magnetic layer magnetically connected to coil, wherein second soft magnetic layer has ring-like shape, spacing distance between second soft magnetic layer and MEF is larger than first soft magnetic layer and MEF, film thickness of second soft magnetic layer is larger than first soft magnetic layer, part of the two first soft magnetic layers overlaps a part of second soft magnetic layer in stacking direction of MEF, first and second soft magnetic layers are magnetically coupled to each other, and MEF is disposed between respective fore ends of two first soft magnetic layers.

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&#x3e;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&#x3e;W1f is established.

Thin film magnetic element having a pair of first soft magnetic layers sandwiching a magnetoresistive effect film and a coil windingly formed about a second soft magnetic layer

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 1.257 Ms&#x3c;Ha&#x3c;12.57 Ms. More preferably, the free magnetic layer is composed of an alloy or a stacked film containing at least one element selected from Co, Ni, Fe, and B.

Thin-film magnetic oscillation element

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.

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.

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.

Magnetic recording medium, magnetic recording and reproducing apparatus, and method for manufacturing magnetic recording medium

A method for manufacturing magnetic recording media is provided, by which a magnetic recording medium that has a recording layer formed in a concavo-convex pattern, a sufficiently flat surface, and good recording/reproducing properties can be manufactured. The method includes the steps of: depositing a first filling material over a workpiece to cover recording elements formed as convex portions of the concavo-convex pattern, and to fill at least part of a concave portion; depositing a detection material over the first filling material; depositing a second filling material over the detection material; and irradiating a surface of the workpiece with a process gas to flatten the surface. In the flattening step, a component of the detection material removed from and flying off the workpiece is detected to stop the irradiation with the process gas based on a result of detecting the component of the detection material.

Method for manufacturing magnetic recording medium

A method for manufacturing a magnetic recording medium is provided, which can manufacture a magnetic recording medium that includes a recording layer having a concavo-convex pattern and has a sufficiently flat surface. The method includes the steps of: forming an object to be processed including a recording layer having a predetermined concavo-convex pattern formed over a substrate and a first mask layer (temporary underlying material) formed at least on recording elements (convex portions) of the recording layer; depositing a filling material on the object to be processed to fill concave portions; removing a part of the filling material by dry etching to expose at least side faces of the first mask layer; and removing the first mask layer by an etching method in which an etching rate of the first mask layer is higher than that of the filling material to flatten a surface.

The magnetic recording medium includes: recording elements formed as the convex portions of the recording layer formed in the predetermined concavo-convex pattern over a substrate; and a filling elements with which a concave portions between the recording elements are filled. A surface concave portion is formed in a surface of the magnetic recording medium above the recording element. The surface concave portion has a cross-sectional shape of which a portion corresponding to a center of the recording element lying thereunder in a width direction thereof is recessed deepest toward the substrate, and has a width monotonically increasing with increase of a distance from the substrate.

Magnetic recording medium with recording layer having a predetermined concavo-convex pattern and magnetic recording and reproducing apparatus

A magnetic recording medium is provided which includes a recording layer formed in a concavo-convex pattern including recording elements formed as convex portions, provides a good flying performance of a magnetic head, and has high reliability. A magnetic recording and reproducing apparatus including that magnetic recording medium and a manufacturing method of that magnetic recording medium are also provided. The magnetic recording medium includes: the recording layer formed in a predetermined concavo-convex pattern over a substrate, the recording elements being formed as convex portions of the concavo-convex pattern; filling elements with which concave portions between the recording elements are filled; a conductive film which has a smaller electric resistivity than the filling elements and is formed over the filling elements; and a protective layer which covers the recording elements and the filling elements and is in contact with an upper surface of the conductive film.

Magnetic recording medium, magnetic recording and reproducing apparatus, and manufacturing method of magnetic recording medium

The magnetic recording medium includes a substrate and a recording layer formed in a predetermined concavo-convex pattern over the substrate, and the recording layer includes recording elements each formed as a convex portion of the recording layer. Surface steps are formed in an inner area including a radially innermost 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 a 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 inner area and the inner area where height of the surface steps is larger than that in the annular area.

In an information recording medium where respective concave parts of a magnetic layer, which is formed on at least one side e of a substrate and in which a predetermined convex/concave pattern has been formed, are filled with non-magnetic material and non-magnetic layers are formed by the non-magnetic material in at least partial regions of respective upper surfaces of respective convex parts of the magnetic layer, the non-magnetic layers are formed so that parts thereof protrude further in a direction in which the convex parts protrude than other parts of the non-magnetic layers.

Information recording medium

On an information recording medium, a data track pattern and a servo pattern composed of a concave/convex pattern including a plurality of convex parts are formed on at least one surface of a substrate and respective concave parts in the concave/convex pattern are filled with non-magnetic material. In the concave/convex pattern that constructs the data track pattern, the respective convex parts are formed concentrically or in a spiral. In the concave/convex pattern that constructs the servo pattern, a unit convex part length along a direction of rotation of the substrate is set so that a value produced by dividing the unit convex part length by a distance from a center of the data track pattern decreases from an inner periphery to an outer periphery.

Information recording medium with concave/convex servo pattern having decreasing unit convex part length ratio

A magnetic recording medium is provided in which a magnetic recording layeris provided in a predetermined concavo-convex pattern on a substrateA, a concave portion in a concavo-convex pattern is filled with a non-magnetic material, and a non-magnetic layerformed of the non-magnetic material positioned at the bottom surface of the concave portion in the non-magnetic materials is formed on a convex portion of the concavo-convex pattern while surface of the convex portion and the concave portion is substantially flattened, and a thickness of the non-magnetic layeris 1 nm or less.

Magnetic recording medium, method of manufacturing the same, and intermediate for magnetic recording medium

A magnetic recording medium in which a recording layer is formed in a predetermined concavo-convex pattern and recording and reproducing apparatus comprising the magnetic recording medium are disclosed. The magnetic recording medium has a high areal density and high reliability since the occurrence of a crash of a magnetic head is suppressed. The magnetic recording medium comprises a recording layer formed over a substrate in a predetermined concavo-convex pattern to form recording elements as a convex portion of the concavo-convex pattern and a non-magnetic filler element filled in a concave portion between the recording elements. In this configuration, the top surface of the filler element is formed in a shape partially recessed toward the substrate side to form a groove having a width smaller than the width of the concave portion on the surface of the magnetic recording medium.

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Tokyo, Japan

Takahiro Suwa