Showa Denko K.k.

Tohoku University

Yuji Murakami

Tetsuya Kanbe

Lei Zhang

Kazuya Niwa

Takayuki Fukushima

Hisato Shibata

Takehiro Yamaguchi

Haruhisa Ohashi

Tomoo Shige

Akira Sakawaki

Katsumi Murofushi

Shin Saito

Chen Xu

Yoshitaka Ishibashi

Shintaro Hinata

Manabu Ueda

Zhipeng Wang

Satoru Nakajima

A magnetic recording medium includes a substrate, an underlayer provided on the substrate, and a magnetic layer provided on the underlayer and having a L1structure and a (001) orientation. The magnetic layer has a granular structure in which an organic compound having a methylene skeleton or a methine skeleton is arranged at grain boundaries of magnetic grains.

Magnetic recording medium, sputtering target, sputtering target manufacturing method, and magnetic storage apparatus

A magnetic recording medium includes: a substrate; a first underlayer; a second underlayer; and a magnetic layer including an alloy having a L1type crystal structure with a (001) orientation. The substrate, the first underlayer, the second underlayer, and the magnetic layer are stacked in this order. The first underlayer is a crystalline layer that includes Mo as a main component. The second underlayer is a crystalline layer that includes a material containing Mo as a main component and that includes an oxide. The content of the oxide in the second underlayer is in a range of from 2 mol % to 30 mol %. The oxide is an oxide of one or more kinds of elements selected from a group consisting of Cr, Mo, Nb, Ta, V, and W.

Magnetic recording medium and magnetic storage apparatus

A magnetic recording medium includes: a substrate; a first underlayer; a second underlayer; and a magnetic layer including an alloy having a L1type crystal structure with a (001) orientation. The substrate, the first underlayer the second underlayer, and the magnetic layer are stacked in this order. The first underlayer is a crystalline layer that includes W as a main component. The second underlayer is a crystalline layer that includes a material containing W as a main component and that includes an oxide. The content of the oxide in the second underlayer is in a range of from 2 mol % to 30 mol %. The oxide is an oxide of one or more kinds of elements selected from a group consisting of Cr, Mo, Nb, Ta, V, and W.

A magnetic recording medium includes: a substrate; an underlayer; and a magnetic layer including an alloy having a L1type crystal structure whose plane orientation is (001). The substrate, the underlayer, and the magnetic layer are stacked in this order. The underlayer includes a first underlayer. The first underlayer is a crystalline layer that includes a material containing Al, Ag, Cu, W, or Mo as a main component element and includes an oxide of the main component element, a content of the oxide of the main component element in the first underlayer being in a range of from 2 mol % to 30 mol %.

The invention provides a magnetic recording medium with an excellent signal-to-noise ratio during reading by reducing the noise produced during writing of data onto the magnetic recording medium, and increasing the signal level. The assisted magnetic recording medium according to one embodiment comprising a substrate, a base layer, and a magnetic layer composed mainly of an alloy with an L1-type crystal structure, the assisted magnetic recording medium having a pinning layer in contact with the magnetic layer, and the pinning layer including Co or an alloy composed mainly of Co.

Assisted magnetic recording medium including a pinning layer and magnetic storage device

A magnetic recording medium includes a substrate, a barrier layer, a crystal grain size control layer, and a magnetic layer that are arranged in this order. The barrier layer includes at least one of oxides, nitrides, and carbides, and the crystal grain size control layer is a crystalline layer including Ag and having an average thickness in a range of 0.1 nm to 1 nm. The barrier layer makes contact with the crystal grain size control layer, and the magnetic layer includes an alloy having a L1crystal structure and a (001) face orientation.

A magnetic recording medium includes a substrate, a first heat sink layer, a barrier layer, a second heat sink layer, and a magnetic layer that are successively stacked. The magnetic layer is made of a material including a first main component that is an alloy having a L1crystal structure and a content of 50 at % or higher, or content of 50 mol % or higher. The barrier layer is made of a material including a second main component that is one of an oxide, a nitride, and a carbide having a content of 50 at % or higher, or content of 50 mol % or higher.

Magnetic storage apparatus including a magnetic recording medium having a barrier layer between two heat sink layers

A magnetic recording medium includes a substrate; a lower base layer formed on the substrate; and a (001) oriented L1magnetic layer formed on the lower base layer and including a first magnetic layer formed on the lower base layer and having a granular structure of magnetic grains and a grain boundary portion, the grain boundary portion containing C, and a second magnetic layer formed on the first magnetic layer and having a granular structure of magnetic grains and a grain boundary portion, the grain boundary portion containing oxide or nitride, the second magnetic layer further containing one or more elements selected from a group consisting of Mg, Ni, Zn, Ge, Pd, Sn, Ag, Re, Au and Pb as an additive.

Magnetic recording medium and magnetic memory device including magnetic layers having granular structure of magnetic grains and grain boundary portion

A magnetic recording medium includes a substrate, multiple underlayers formed on the substrate, and a magnetic layer formed on the multiple underlayers. A main component of the magnetic layer is an alloy having a L1structure. At least one of the multiple underlayers is a crystalline underlayer containing W. The W is a main component of the crystalline underlayer. The crystalline underlayer further contains 1 mol % or more to 20 mol % or less of one or more kinds of elements selected from B, Si, and C. A barrier layer including a material having a NaCl structure is formed between the crystalline underlayer and the magnetic layer.

A magnetic recording medium includes a substrate, a magnetic layer including an alloy having a L1type crystal structure as a main component thereof, and a plurality of underlayers arranged between the substrate and the magnetic layer. The plurality of underlayers include a first underlayer including two or more elements selected from a group consisting of Ta, Nb, Ti, and V, and one or more elements selected from a group consisting of W and Mo, and a second underlayer including MgO.

[object Object]

A thermally-assisted magnetic recording medium or a microwave-assisted magnetic recording medium includes: an orientation control layer () that is formed on a substrate (); an underlayer () that is formed on the orientation control layer (); and a magnetic layer () that is formed on the underlayer () and contains an alloy having an L1type crystal structure as a main component, in which the underlayer () includes an MgO underlayer () that contains MgO and has a (100) orientation and a nitride underlayer () that contains at least one nitride selected from the group consisting of TaN, NbN, and HfN and has a (100) orientation.

Magnetic recording medium and magnetic recording and reproducing apparatus

A magnetic recording medium includes a substrate, a magnetic layer including an alloy having an L1type crystal structure as a main component thereof, and a plurality of underlayers arranged between the substrate and the magnetic layer. The plurality of underlayers include at least one crystalline underlayer which has a (100) orientation, and includes W as a main component thereof and one or more kinds of elements selected from a group consisting of Fe, Ni, Co, Hf, Zr, Y, Be, Ce, La, and Sc.

A magnetic recording medium includes a substrate, a magnetic layer including a FePt alloy having a L1type structure, and a plurality of underlayers arranged between the substrate and the magnetic layer, wherein at least one of the plurality of underlayers includes TiO.

A magnetic recording medium includes a substrate, a magnetic layer including an alloy having an L1type crystal structure as a main component thereof, a plurality of underlayers arranged between the substrate and the magnetic layer, and a barrier layer made of a material having an NaCl structure. The plurality of underlayers include at least one crystalline underlayer including Mo as a main component thereof, and at least one of Si and C in a range of 1 mol % to 20 mol % and an oxide in a range of 1 vol % to 50 vol %. The barrier layer is provided between the magnetic layer and the at least one crystalline underlayer including Mo.

A thermally assisted magnetic recording medium () includes a substrate (), an underlayer () that is formed above the substrate (), and a magnetic layer () that is formed on the underlayer () and contains an alloy having an L1structure as a main component. The underlayer () is formed by continuously laminating a first underlayer () having a BCC structure with a lattice constant that is 0.302 to 0.332 nm, a second underlayer () that has a NaCl structure including C, and a third underlayer () that is composed of MgO.

Growing community of inventors

Chiba, Japan

Yuji Murakami