Tdk Corporation

Shogo Yamada

Tatsuo Shibata

Tomoyuki Sasaki

Minoru Ota

Yukio Terasaki

Yugo Ishitani

Shogo Yonemura

Toshiki Gushi

A magnetic domain wall motion element includes a first ferromagnetic layer, in-plane wiring, and first, second and third via wirings. A position of the in-plane wiring in a stacking direction is different from that of the first ferromagnetic layer. The first via wiring connects the first ferromagnetic layer and in-plane wiring. The second via wiring is connected to the in-plane wiring at a different position from the first. The third via wiring is connected to the in-plane wiring at a different position from the first and second. When positions of the second and the third via wirings are projected on an axis passing through a center of the first via wiring when viewed in the stacking direction and extending in a second direction, the first via wiring is interposed between projection points of the second and third via wirings to the axis in the second direction.

Magnetic domain wall motion element and magnetic array

A magnetic domain wall moving layer, reference layer, non-magnetic layer, a first, second, and third electrode. Magnetic domain wall moving layer includes first area wherein an orientation direction of magnetization is fixed, second area wherein orientation direction of magnetization is fixed in direction different from that of first area, and third area sandwiched between first and second areas wherein orientation direction of magnetization is changeable. First electrode is connected to first area. Second electrode is connected to second area. In magnetic domain wall moving element, a read current flows between second and third electrodes. In first direction, a center of third area in first direction is between center of first connection surface of third electrode and reference layer in first direction and center of second connection surface of second electrode and magnetic domain wall moving layer in first direction.

Magnetic domain wall moving element, magnetic array, and neuromorphic device

A magnetic domain wall moving element includes a first ferromagnetic layer, non-magnetic layer, second ferromagnetic layer, first magnetization fixed part, second magnetization fixed part, first surface layer and second surface layer. The first and second ferromagnetic layer sandwich the non-magnetic layer, the second ferromagnetic layer has a region having a magnetic domain wall formed therein, the first magnetization fixed part contacts second ferromagnetic layer, the second magnetization fixed part contacts second ferromagnetic layer at a position different from that of the first magnetization fixed part, the first is thicker than the second magnetization fixed part, the first surface layer contacts the first magnetization fixed part's first surface, the second surface layer contacts the second magnetization fixed part's first surface, and a constituent atom of a portion of the first surface layer in contact with the first magnetization fixed part are different from a constituent atom of the second surface layer.

Magnetic domain wall moving element and magnetic array

A magnetic domain wall movement element includes a magnetic recording layer which includes a ferromagnetic material; a non-magnetic layer which is laminated on the magnetic recording layer; and a magnetization reference layer which is laminated on the non-magnetic layer, in which the magnetic recording layer has a first ferromagnetic layer, a spacer layer, and a second ferromagnetic layer in order from the non-magnetic layer, a magnetization of the first ferromagnetic layer and a magnetization of the second ferromagnetic layer are antiferromagnetically coupled, and an electrical resistivity of the first ferromagnetic layer is higher than the electrical resistivity of the second ferromagnetic layer.

Magnetic domain wall movement element including resistivity varying ferromagnetic layers

A magnetic domain wall movement element includes a magnetoresistance effect part, a first electrode, a second electrode, a third electrode, a first magnetization fixed layer, and a second magnetization fixed layer. The magnetoresistance effect part includes a reference layer, a magnetic domain wall movement layer, and a non-magnetic layer. The magnetic domain wall movement layer has a first region and second region in which a magnetization direction is fixed, and a third region in which a magnetization direction is variable. The reference layer overlaps at least part of the first region and the second region in a plan view in a first direction, and at least part of the first region and the second region is shorter than the third region in a third direction orthogonal to the first direction and the second direction.

Magnetic domain wall movement element and magnetic array

A magnetoresistance effect element includes a magnetic recording layer which includes a ferromagnetic material, a non-magnetic layer laminated on the magnetic recording layer, and a magnetization reference layer which is laminated on the non-magnetic layer. The magnetic recording layer includes a first ferromagnetic layer, a spacer layer, and a second ferromagnetic layer in order from the non-magnetic layer. The first ferromagnetic layer and the second ferromagnetic layer are antiferromagnetically coupled to each other. The magnetic recording layer has a central region in which a product of a film thickness and saturation magnetization of the first ferromagnetic layer is greater than a product of a film thickness and saturation magnetization of the second ferromagnetic layer, and an outer region in which the product of the film thickness and the saturation magnetization of the first ferromagnetic layer is smaller than the product of the film thickness and the saturation magnetization of the second ferromagnetic layer.

Magnetoresistance effect element and magnetic recording array

A neuromorphic device includes: first and second element groups, in which each includes magnetic domain wall movement elements, each of which includes magnetic domain wall movement and ferromagnetic layers, and a non-magnetic layer between the magnetic domain wall movement and ferromagnetic layers, a length of the magnetic domain wall movement layer of each of the magnetic domain wall movement elements belonging to the first element group in a longitudinal direction is shorter than a length of the magnetic domain wall movement layer of each of the magnetic domain wall movement elements belonging to the second element group in the longitudinal direction, and a resistance changing rate when a predetermined pulse is input is higher for each of the magnetic domain wall movement elements belonging to the first element group than for each of the magnetic domain wall movement elements belonging to the second element group.

Neuromorphic device

An integrated device includes: a substrate; and a laminated structural body. The substrate has a plurality of switching elements. The laminated structural body has a plurality of magnetic elements having a first element group disposed in a first hierarchical layer and a second element group disposed in a second hierarchical layer. Each of the plurality of magnetic elements includes a conductive layer and a laminated body including a ferromagnetic layer. The plurality of switching elements include a plurality of first switching elements connected to first ends of the conductive layers and a plurality of second switching elements connected to second ends of the conductive layers. A first switching element connected to a second magnetic element belonging to a second element group which is present between a first switching element and a second switching element connected to a first magnetic element belonging to a first element group.

Integrated device and neuromorphic device

A magnetic domain wall displacement element includes a first ferromagnetic layer, a second ferromagnetic layer extending in a second direction and magnetically recordable, a nonmagnetic layer, and a first conductive part having a first intermediate layer and a second conductive part having a second intermediate layer, in which the first intermediate layer is sandwiched between first and second magnetization regions and exhibiting first and second magnetization directions, the second intermediate layer is sandwiched between a third magnetization region and exhibiting the second magnetization direction and a fourth magnetization region exhibiting the first magnetization direction in the first direction, and an area of the first magnetization region is larger than an area of the second magnetization region and an area of the third magnetization region is smaller than an area of the fourth magnetization region in a cross section in the first direction and the second direction.

Magnetic domain wall displacement element, magnetic recording array, and semiconductor device

According to an embodiment, there is provided an integrated device including: a substrate; and a laminated structure stacked on the substrate, in which the laminated structure includes a first element group and a second element group disposed at a position farther from the substrate than the first element group, each of the first element group and the second element group includes a plurality of domain wall movement elements, each of the plurality of domain wall movement elements includes a domain wall movement layer, a ferromagnetic layer, and a non-magnetic layer interposed between the domain wall movement layer and the ferromagnetic layer, and each of the domain wall movement elements belonging to the second element group has a lower critical current density required for moving a domain wall of the domain wall movement layer than each of the domain wall movement elements belonging to the first element group.

A magnetic domain wall displacement type magnetic recording element which comprises: a first magnetization fixed part which is stacked in a first direction, a magnetic recording layer which includes a magnetic domain wall and extends in a second direction which crosses with the first direction, a non-magnetic layer which is provided between the first magnetization fixed part and the magnetic recording layer, and a first via part which is electrically connected to the magnetic recording layer, wherein at least a part of the first via part is located at a position which is apart from the first magnetization fixed part in the second direction in planar view observed from the first direction, the magnetic recording layer includes a first part which has a position where the first magnetization fixed part overlaps with the magnetic recording layer in planar view observed from the first direction, and a width of the first via part in a third direction which is orthogonal to the second direction is larger than a width of said position of the first part of the magnetic recording layer.

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Tokyo, Japan

Shogo Yamada