Kabushiki Kaisha Toshiba

Showa Denko K.k.

Other

Tdk Corporation

Toshiba Corporation

Soichi Oikawa

Hiroshi Sakai

Kenji Shimizu

Takashi Hikosaka

Akira Sakawaki

Takeshi Iwasaki

Futoshi Nakamura

Tomoyuki Maeda

Katsuhiko Koui

Kenichiro Yamada

Hiroaki Yoda

Yushi Kato

Hitoshi Iwasaki

Masayuki Takagishi

Tomomi Funayama

Masahiro Takashita

Mizue Ishikawa

Yoshiaki Saito

Akira Kikitsu

Hideo Ogiwara

Mariko Shimizu

Mariko Kitazaki

Min Li

Yuchen Zhou

Kunliang Zhang

Kazuo Kobayashi

Hiro Mochizuki

Masatoshi Sakurai

Tomoaki Inokuchi

Akihiko Takeo

Akira Watanabe

Yousuke Isowaki

Yoichiro Tanaka

Hui Yang

According to one embodiment, a magnetic memory device includes a conductive member, a first magnetic layer, a first counter magnetic layer, and a first nonmagnetic layer. The conductive member includes a first portion, a second portion, and a third portion between the first portion and the second portion. The first counter magnetic layer is provided between the third portion and the first magnetic layer in a first direction crossing a second direction. The second direction is from the first portion toward the second portion. The first nonmagnetic layer is provided between the first magnetic layer and the first counter magnetic layer. The third portion includes a first position, and a second position between the first position and the first counter magnetic layer in the first direction. A second concentration of boron at the second position is lower than a first concentration of boron at the first position.

Magnetic memory device

According to one embodiment, a magnetic memory device includes a first magnetic region, a first counter magnetic region, and a first nonmagnetic region provided between the first magnetic region and the first counter magnetic region. The first magnetic region includes a first magnetic film, a second magnetic film, and an intermediate film. The first magnetic film is provided between the second magnetic film and the first nonmagnetic region. The intermediate film includes Ru and is provided between the first magnetic film and the second magnetic film. A distance along a first direction between the first magnetic film and the second magnetic film is not less than 1.8 nm and not more than 2.2 nm. The first direction is from the first counter magnetic region toward the first magnetic region.

According to one embodiment, a magnetic memory device includes a conductive member, a first magnetic layer, a second magnetic layer, and a first nonmagnetic layer. The conductive member includes a first layer. The first layer includes at least one selected from the group consisting of HfN having a NaCl structure, HfN having a fcc structure, and HfC having a NaCl structure. The first magnetic layer is separated from the first layer in a first direction. The second magnetic layer is provided between the first layer and the first magnetic layer. The first nonmagnetic layer is provided between the first magnetic layer and the second magnetic layer.

A magnetic memory according to an embodiment includes: first to third terminals; a nonmagnetic conductive layer including first to third regions, the second region being disposed between the first and third regions, the first region being electrically connected to the first terminal, and the third region being electrically connected to the second terminal; and a magnetoresistive element disposed to correspond to the second region, including a first magnetic layer electrically connected to the third terminal, a second magnetic layer disposed between the first magnetic layer and the second region, and a nonmagnetic layer disposed between the first and second magnetic layers, the conductive layer including at least one of an alloy including Ir and Ta, an alloy including Ir and V, an alloy including Au and V, an alloy including Au and Nb, or an alloy including Pt and V, each of the alloys having an fcc structure.

Magnetic memory

According to one embodiment, a magnetic memory device includes a conductive layer, a first magnetic layer, a second magnetic layer, a first nonmagnetic layer, and a controller. The conductive layer includes first and second portions, and a third portion between the first and second portions. The conductive layer includes a first metal and boron. The first magnetic layer is separated from the third portion in a first direction crossing a second direction. The second magnetic layer is provided between the third portion and the first magnetic layer. The first nonmagnetic layer is provided between the first and second magnetic layers. The controller is electrically connected to the first and second portions. The controller supplies a current to the conductive layer. The first metal includes at least one selected from the group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu.

According to one embodiment, a magnetic memory device includes a conductive layer, first and second magnetic layers, a first nonmagnetic layer and a controller. The conductive layer includes first and second portions, and a third portion positioned between the first and second portions. The conductive layer includes a first metal. The first magnetic layer is separated from the third portion. The second magnetic layer is provided between the third portion and the first magnetic layer. The first nonmagnetic layer is provided between the first and second magnetic layers. The controller is electrically connected to the first and second portions. The second magnetic layer has first and second lattice lengths. The first lattice length is longer than the second lattice length. The controller implements a first operation of supplying a first current to the conductive layer, and a second operation of supplying a second current to the conductive layer.

According to one embodiment, a magnetic memory device includes a conductive layer, a first magnetic layer, a second magnetic layer, a first nonmagnetic layer, and a controller. The conductive layer includes a first portion, a second portion, and a third portion between the first and second portions. The first magnetic layer is separated from the third portion. The second magnetic layer is provided between the third portion and the first magnetic layer. The first nonmagnetic layer is provided between the first and second magnetic layers. The controller is electrically connected to the first and second portions. The third portion includes a first region and a second region. The second region is provided between the first region and the second magnetic layer. The controller implements a first operation of supplying a first current to the conductive layer, and a second operation of supplying a second current to the conductive layer.

A magnetic memory of an embodiment includes: first through third terminals; a conductive layer including first through third portions, the first portion being located between the second and third portions, the second and third portions being electrically connected to the first and second terminals respectively; and a magnetoresistive element including: a first magnetic layer electrically connected to the third terminal; a second magnetic layer disposed between the first magnetic layer and the first portion; a first nonmagnetic layer disposed between the first magnetic layer and the second magnetic layer; a third magnetic layer disposed between the first nonmagnetic layer and the second magnetic layer; and a second nonmagnetic layer disposed between the second magnetic layer and the third magnetic layer, a sign of a spin Hall angle of the second nonmagnetic layer being different from a sign of a spin Hall angle of the conductive layer.

According to one embodiment, a magnetic recording medium includes a silicon oxide underlayer having a recess pattern having a plurality of recesses, a nonmagnetic underlayer having a first hole pattern having a plurality of holes corresponding to the recess pattern, and a magnetic recording layer having a second hole pattern having a plurality of holes connected with the first hole pattern. The silicon oxide underlayer, the nonmagnetic underlayer, and the magnetic recording layer are formed in order on the substrate.

Magnetic recording medium, method for manufacturing magnetic recording medium, and magnetic recording/reproduction apparatus

According to one embodiment, a perpendicular magnetic recording medium includes a substrate, and a multilayered magnetic recording layer formed on the substrate by alternately stacking two or more magnetic layers and two or more nonmagnetic layers. The magnetic layers and nonmagnetic layers of the multilayered magnetic recording layer are continuous layers. The magnetic layer includes a magnetic material portion, and a plurality of pinning sites dispersed in the magnetic material portion and made of a nonmagnetic metal different from a nonmagnetic material as a main component of the nonmagnetic layer. This perpendicular magnetic recording medium has magnetic characteristics by which a gradient &#x3b1; of a magnetization curve near the coercive force is 5 or more.

Magnetic recording medium with a plurality of pinning portions in the magnetic layer

According to one embodiment, a magnetic recording head includes a main magnetic pole generating a recording magnetic field in a magnetic recording medium, a return yoke paired with the main magnetic pole, and a spin torque oscillator interposed between the main magnetic pole and the return yoke and including a spin injection layer, an oscillation layer, a nonmagnetic metal layer, and spin assist layer stacked in this order, wherein the nonmagnetic metal layer includes at least one metal selected from the group consisting of Cu, Au, Ag, Al, Pd, Pt, Os, and Ir, and the spin assist layer is a soft magnetic layer whose saturation magnetic flux density (Bs), diamagnetic field coefficient (N) and gap magnetic field (Hg) show a relationship expressed by Bs&#xd7;N&#x3e;Hg.

Magnetic recording head and magnetic recording apparatus

According to one embodiment, a thermally assisted magnetic recording method performs heating at a temperature higher than the ambient temperature of the perpendicular recording medium and lower than a temperature at which a nucleation magnetic field Hn of the recording portion is 0, decreases a coercive force Hc of a recording portion by heating a perpendicular recording medium, and records magnetic information by applying a recording magnetic field from a recording magnetic pole to the recording portion having the decreased coercive force.

Thermally assisted magnetic recording medium and thermally assisted magnetic recording apparatus

According to one embodiment, a bit patterned medium includes a substrate, and a magnetic recording layer disposed above the substrate and including patterns of protrusions. Each of the protrusions contains a plurality of crystal grains. An average distance between the crystal grains is 0.5 to 3.0 nm in each of the protrusions. The protrusions include first protrusions each having a length of 1 &#x3bc;m or more in a radial direction of the medium and second protrusions each having a length in the radial direction shorter than the length of the first protrusion in the radial direction. Each of the first protrusions has a nucleation field Hn for magnetization reversal and a coercive force Hc satisfying the inequalities, Hn&#x2267;1.5 kOe and 0.5 kOe&#x2266;Hc&#x2212;Hn&#x2266;1.5 kOe.

Magnetic recording medium

A magnetic recording head includes a magnetic pole, a spin torque oscillator, a first shield and a second shield. The magnetic pole has an air-bearing surface. The spin torque oscillator is provided so that a first side of the spin torque oscillator faces the magnetic pole in a first direction parallel to the air-bearing surface. The first shield includes a granular magnetic material, and is provided so that two portions of the first shield sandwich the spin torque oscillator in a second direction which is parallel to the air-bearing surface and perpendicular to the first direction. The second shield is provided on a second side of the spin torque oscillator opposite to the first side.

Magnetic recording head and magnetic recording/reproducing apparatus using the same

A spin transfer (torque) oscillator (STO) with a non-magnetic spacer formed between a spin injection layer (SIL) and a field generation layer (FGL), and with an interfacial layer comprised of FeCowhere v is from 5 to 100 atomic % formed between the SIL and non-magnetic spacer is disclosed. A composite seed layer made of Ta and a metal layer having a fcc(111) or hcp(001) texture is used to enhance perpendicular magnetic anisotropy (PMA) in the STO device. The interfacial layer quenches SIL oscillations and thereby stabilizes the SIL against FGL oscillations. The interfacial layer preferably has a thickness from 5 to 50 Angstroms and enhances amplitude (dR/R) in the STO device. The STO device may have a top SIL or bottom SIL configuration. The SIL is typically a laminated structure such as (Co/Ni)where x is between 5 and 50.

Growing community of inventors

Hachioji, Japan

Soichi Oikawa