Crocus-technology Sa

Other

Sebastien Bandiera

Ioan Lucian Prejbeanu

Quentin Stainer

A MLU cell for sensing an external magnetic field, including a magnetic tunnel junction including a sense layer having a sense magnetization adapted to be oriented by the external magnetic field; a reference layer having a reference magnetization; a tunnel barrier layer; a biasing layer having a biasing magnetization and a biasing antiferromagnetic layer pinning the biasing magnetization substantially parallel to the pinned reference magnetization at a low threshold temperature and freeing it at a high threshold temperature. A biasing coupling layer is between the sense layer and the basing layer and configured for magnetically coupling the biasing layer and the sense layer such that the sense magnetization is oriented substantially perpendicular to the pinned biasing magnetization and to the pinned reference magnetization. The present disclosure further concerns a magnetic sensor device for sensing an external magnetic field, including a plurality of the MLU cells.

MLU cell for sensing an external magnetic field and a magnetic sensor device comprising the MLU cell

A magnetoresistive element including: a storage layer having a first storage magnetostriction; a sense layer having a first sense magnetostriction; and a barrier layer between and in contact with the storage and sense layer. The magnetoresistive element also includes a compensating ferromagnetic layer having a second magnetostriction different from the first storage magnetostriction and/or sense magnetostriction, and adapted to compensate the first storage magnetostriction and/or the first sense magnetostriction so that a net magnetostriction of the storage layer and/or sense layer is adjustable between &#x2212;10 ppm and +10 ppm or more negative than &#x2212;10 ppm by adjusting a thickness of the compensating ferromagnetic layer. The present disclosure also concerns a magnetic device comprising the magnetoresistive element.

Magnetoresistive element having an adjustable magnetostriction and magnetic device comprising this magnetoresistive element

A magnetic logic unit (MLU) cell for sensing magnetic fields, including: a magnetic tunnel junction including a storage layer having a storage magnetization, a sense layer having a sense magnetization; a tunnel barrier layer between the storage layer and the sense layer; and a pinning layer pinning the storage magnetization at a low threshold temperature and freeing it at a high threshold temperature. The sense magnetization is freely alignable at the low and high threshold temperatures and the storage layer induces an exchange bias field magnetically coupling the sense layer such that the sense magnetization tends to be aligned antiparallel or parallel to the storage magnetization. The tunnel barrier layer is configured for generating an indirect exchange coupling between the tunnel barrier layer and the sense layer providing an additional exchange bias field.

Magnetic logic unit (MLU) cell for sensing magnetic fields with improved programmability and low reading consumption

A programmable magnetic device for generating random numbers during a programming operation, including an array of a plurality of magnetic tunnel junctions. Each magnetic tunnel junction includes a reference layer having a reference magnetization; a tunnel barrier layer; and a storage layer having a storage magnetization. The programmable magnetic device is arranged such that, during the programming operation, the storage magnetization is orientable in an unstable magnetization configuration and relaxable randomly in one of a plurality of stable or metastable configurations from the unstable magnetization configuration.

MRAM-based programmable magnetic device for generating random numbers

A magnetic sensor device for sensing an external magnetic field includes a plurality of MLU cells, each MLU cell having a magnetic tunnel junction including a sense layer having a sense magnetization freely orientable in the external magnetic field, a storage layer having a storage magnetization; and a tunnel barrier layer between the sense layer and the storage layer. The magnetic sensor device includes a stress inducing device configured for applying an anisotropic mechanical stress on the magnetic tunnel junction such as to induce a stress-induced magnetic anisotropy on at least one of the sense layer and the storage layer. The stress-induced magnetic anisotropy induced by the stress inducing device corresponds substantially to a net magnetic anisotropy of the at least one of the sense layer and the storage layer. The magnetic sensor device can be programmed easily and has improved sensitivity.

MLU based magnetic sensor having improved programmability and sensitivity

A magnetic sensor cell includes a magnetic tunnel junction including a reference layer having a reference magnetization oriented parallel to the plane of the reference layer, a sense layer having a sense magnetization, and a tunnel barrier layer between the sense and reference layers. A magnetic device is configured for providing a sense magnetic field for aligning the sense magnetization. The sense layer magnetization is orientable between a direction parallel to the plane of the sense layer and a direction perpendicular to the plane of the sense layer when the sense magnetic field is provided. The magnetic sensor cell can be used for sensing an external magnetic field including a component oriented parallel to the plane of the sense layer and a component oriented perpendicular to the plane of the sense layer.

Magnetic sensor cell for measuring three-dimensional magnetic fields

Method for sensing an external magnetic field using a magnetic sensor cell including: a magnetic tunnel junction including a reference layer having a reference magnetization oriented parallel to the plane of the reference layer, a sense layer having a sense magnetization, and a tunnel barrier layer between the sense and reference layers. A field line is configured for passing a field current for providing a sense magnetic field adapted for aligning the sense magnetization. The sense layer magnetization is orientable between a direction parallel to the plane of the sense layer and a direction perpendicular to the plane of the sense layer when the sense magnetic field is provided. The external magnetic field includes an in-plane component oriented parallel to the plane of the sense layer and an out-of-plane component perpendicular to the plane of the sense layer. The method includes sensing the out-of-plane component; and sensing the in-plane component.

Method for measuring three-dimensional magnetic fields

A self-referenced MRAM cell comprises a first portion of a magnetic tunnel junction including a storage layer; a second portion of the magnetic tunnel junction portion including a tunnel barrier layer, a sense layer and a seed layer; the seed layer comprising a material having high spin-orbit coupling such that passing a sense current along the plane of the sense layer and/or seed layer exerts a spin-orbit torque adapted for switching a sense magnetization of the sense layer. A memory device comprising a plurality of the MRAM cells and a method for operating the memory device are also disclosed.

Self-referenced memory device and method using spin-orbit torque for reduced size

MRAM cell including a magnetic tunnel junction including a reference layer, a storage layer having a storage magnetization, a tunnel barrier layer between the reference and the storage layers; and an antiferromagnetic layer exchange-coupling the storage layer such as to pin the storage magnetization at a low temperature threshold and free it at a high temperature threshold. The storage layer includes a first ferromagnetic layer in contact with the tunnel barrier layer, a second ferromagnetic layer in contact with the antiferromagnetic layer, and a low saturation magnetization storage layer including a ferromagnetic material and a non-magnetic material. The MRAM cell can be written with improved reliability.

Thermally-assisted MRAM cells with improved reliability at writing

Magnetic element including a first magnetic layer having a first magnetization; a second magnetic layer having a second magnetization; a tunnel barrier layer between the first and the second magnetic layers; and an antiferromagnetic layer exchanged coupling the second magnetic layer such that the second magnetization is pinned below a critical temperature of the antiferromagnetic layer, and can be freely varied when the antiferromagnetic layer is heated above that critical temperature. The magnetic element also includes an oxygen gettering layer between the second magnetic layer and the antiferromagnetic layer, or within the second magnetic layer. The magnetic element has reduced insertion of oxygen atoms in the antiferromagnetic layer and possibly reduced diffusion of manganese in the second magnetic layer resulting in an enhanced exchange bias and/or enhanced resistance to temperature cycles and improved life-time.

Growing community of inventors

Auburn Hills, MI, United States of America

Sebastien Bandiera