Commissariat a L'energie Atomique

Centre National De La Recherche Scientifique

Commissariat &#xc0; L'&#xc9;nergie Atomique Et Aux &#xc9;nergies Alternatives

Bernard Rodmacq

Bernard Dieny

Olivier Redon

Stéphane Auffret

Jérôme Moritz

Franck Ernult

Stéphane Landis

Jean Mouchot

Sebastien Bandiera

Lavinia Elena Nistor

Vincent Baltz

Alberto Bollero

Philippe Gerard

Andre Pierrot

A magnetic stack with out of plane magnetisation, the magnetic stack including: a first magnetic layer constituted of one or more materials selected from the following group: cobalt, iron and nickel and magnetic alloys based on the materials; a second layer constituted of a metallic material able to confer to an assembly formed by the first and the second layers a perpendicular anisotropy of interfacial origin when the second layer has a shared interface with the first layer; and a third layer deposited on the first layer, the second layer being deposited on the third layer, the third layer being constituted of a metallic material having a miscibility less than 10% with the material of the first layer.

Magnetic stack and memory cell comprising such a stack

A three-layer magnetic element comprises, on a substrate, a first oxide, hydride or nitride layer O having a metal magnetic layer M mounted thereon, the latter having either a second oxide, hydride or nitride layer O', or a non-ferromagnetic metal layer M&#x2032; mounted thereon. Layer M is continuous, has a thickness of 1 to 5 nm and the magnetization thereof is parallel to the layer plane in the absence of layers O and O&#x2032;. There is, for a range of temperature equal to or greater than ambient temperature, interfacial magnetic anisotropy perpendicular to the layer plane on interfaces O/M and M/O&#x2032; that is capable of decreasing the effective demagnetizing field of layer M or orienting the magnetization of layer M in a manner substantially perpendicular to the layer plane.

Three-layer magnetic element, magnetic field sensor, magnetic memory and magnetic logic gate using such an element

The present invention relates to a magnetic recording medium (). The invention finds a particularly interesting application in the field of data stored on hard disks. The medium () comprises an assembly of magnetic zones disposed on a substrate (), each magnetic zone comprising at least one first (C') and one second (C&#x2032;) stacked magnetic layers separated from each other by a non-magnetic layer (NM&#x2032;). In addition, said first magnetic layer (C&#x2032;) presents magnetization substantially oriented parallel to the plane of said substrate () and said second magnetic layer (C&#x2032;) presents magnetization substantially oriented perpendicular to the plane of said substrate ().

Magnetic recording medium

This magnetic multilayer device comprises, on a substrate, an alternating sequence of magnetic metallic layers M and oxide, hydride or nitride layers O. The number of layers M equals at least two. The layers M are continuous. There is interfacial magnetic anisotropy perpendicular to the plane of the layers at the level of the M/O interfaces.

Magnetic multilayer device, method for producing such a device, magnetic field sensor, magnetic memory and logic gate using such a device

Magnetoresistive device comprising a spin valve formed from a stack of layers including at least two magnetic layers for which a relative orientation of their magnetisation directions are capable varying under influence of a magnetic field; at least one discontinuous dielectric or semiconducting layer with electrically conducting bridges at least partially passing through a thickness of the dielectric or semiconducting layer, the bridges configured to locally concentrate current that passes transversely through the stack; and means for circulating a current in the spin valve transverse to the plane of the layers, characterised in that the dielectric or semiconducting layer with electrically conducting bridges is arranged inside one of the magnetic layers.

Spin valve magnetoresistive device with conductive-magnetic material bridges in a dielectric or semiconductor layer alternatively of magnetic material

A thin-film magnetic device comprises, on a substrate, a composite assembly deposited by cathode sputtering and consists of a first layer made of a ferromagnetic material with a high rate of spin polarization, the magnetization of which is in plane in the absence of any electric or magnetic interaction, a second layer made of a magnetic material with high perpendicular anisotropy, the magnetization of which is outside the plane of said layer in the absence of any electric or magnetic interaction, and coupling of which with said first layer induces a decrease in the effective demagnetizing field of the entire device, a third layer that is in contact with the first layer via its interface opposite to that which is common to the second layer and made of a material that is not magnetic and not polarizing for electrons passing through the device.

Thin-film magnetic device with strong spin polarization perpendicular to the plane of the layers, magnetic tunnel junction and spin valve using such a device

The magnetic device comprises a least two layers made of a magnetic material that are separated by at least one interlayer made of a non-magnetic material. The layers made of a magnetic material each have magnetization oriented substantially perpendicular to the plane of the layers. The layer of non-magnetic material induces an antiferromagnetic coupling field between the layers made of a magnetic material, the direction and amplitude of this field attenuating the effects of the ferromagnetic coupling field of magnetostatic origin that occurs between the magnetic layers.

Magnetic device having perpendicular magnetization and interaction compensating interlayer

An information storage medium with an array of laterally magnetised dots, as well as a process for producing this medium is disclosed. Each dot () contains at least one magnetic domain formed by a thin layer () of at least a magnetic material laterally covering this flat material and deposited at oblique incidence relative to the normal (z) to the plane () of the array. The invention applies in particular to computer hard drives.

Information storage medium with laterally magnetised dot array, and process for producing said medium

A magnetoresistive device with a spin valve formed from a stack of layers including at least two magnetic layers for which the relative orientation of their magnetization directions can vary under the influence of a magnetic field, and comprising means of circulating a current in the spin valve transverse to the plane of the layers. The spin valve comprises at least one discontinuous dielectric or semiconducting layer in the stack, with electrically conducting bridges passing through the thickness of the dielectric or semiconducting layer, these bridges being designed to locally concentrate the current that passes transversely through the stack. Application particularly suitable for magnetic read heads, and random access memories.

Spin valve magnetoresistive device with conductive-magnetic material bridges in a dielectric or semiconducting layer alternatively of magnetic material

An information storage medium with an array of laterally magnetized dots, as well as a process for producing this medium is disclosed. Each dot () contains at least one magnetic domain formed by a thin layer () of at least a magnetic material laterally covering this flat material and deposited at oblique incidence relative to the normal (z) to the plane () of the array. The invention applies in particular to computer hard drives.

Data storage medium with laterally magnetized pad and method for making same

A magnetic device including at least a memory cell having a first magnetic layer with a fixed magnetization direction. The first magnetic layer spin polarizes a writing current of electrons. The memory cell includes a second magnetic layer having a three-layered stack with a variable magnetization direction. An insulating or semi-conduction layer is formed between the first and second magnetic layers. The variable magnetization direction is oriented by spins of a spin polarized writing current. The three-layered stack includes two magnetic layers separated by a non-magnetic conducting layer. The first magnetic layer aligns the variable magnetization direction with the fixed magnetization direction by directing an incident writing current of electrons perpendicular through the first magnetic layer and then perpendicular through the second magnetic layer. The first magnetic layer opposes the variable magnetization direction with the fixed magnetization direction by directing another incident writing current of electrons perpendicular through the second magnetic layer and then perpendicular through the first magnetic layer to.

Three-layered stacked magnetic spin polarization device with memory

A magnetic spin polarizing a magnetization rotation device with a memory and a writing process using such a device. The device is configured to include an apparatus for polarizing the spin of electrons, including a magnetic layer having magnetization perpendicular to the plane of magnetization of respective first and second magnetic layers. The magnetization of the second magnetic layer rotates within a plane, which is either the plane of the layer or a perpendicular plane.

Magnetic spin polarization and magnetization rotation device with memory and writing process, using such a device

Multilayer magnetic transducer and structure and process for the production of the structure. The magnetic structure only has one stack of layers of a magnetic material separated by layers of a non-magnetic metallic material having a thickness such that there is an anti-ferromagnetic coupling between the magnetic layers, the magnetic material being chosen from among the alloys FeNi, FeNiCo, and NiCo and the non-magnetic material is silver.

Growing community of inventors

Veurey Voroize, France

Bernard Rodmacq