Patents by Inventor Lucian Prejbeanu

Lucian Prejbeanu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230358826
    Abstract: A method for measuring the intensity of an external magnetic field by using a magnetic memory point including a storage layer having a magnetisation switchable between two magnetisation directions substantially perpendicular to the plane of the layer; a reference layer having a fixed magnetisation perpendicular to the plane of the layer; and a tunnel barrier layer separating the storage layer and the reference layer; the method including successively applying a plurality of currents or voltages of different amplitudes to the memory point until switching of the magnetisation direction of the storage layer takes place to determine a minimum switching current value of the magnetisation direction of the storage layer or a minimum switching voltage value of the magnetisation direction of the storage layer, and determining the intensity of the external magnetic field to be measured from the minimum switching current value or the minimum switching voltage value.
    Type: Application
    Filed: August 24, 2021
    Publication date: November 9, 2023
    Inventors: Ricardo SOUSA, Ioan-Lucian PREJBEANU
  • Publication number: 20220085285
    Abstract: A method for manufacturing a spintronic device including a non-magnetic spacer, a reference layer and a storage layer including a magnetic pillar, the method including depositing at least one sacrificial layer; forming at least one flared cavity, traversing the sacrificial layer; depositing at least one magnetic layer in the cavity; eliminating the excess of magnetic layer outside of the cavity; removing the dielectric layer in order to form at least one magnetic pillar forming all or part of the storage layer; depositing at least the non-magnetic spacer and the reference layer; filling the spaces between the magnetic pillars with a dielectric material; carrying out a polishing; forming an electrical contact on the surface of the element surmounting the magnetic pillar.
    Type: Application
    Filed: December 20, 2019
    Publication date: March 17, 2022
    Inventors: Bernard DIENY, Ioan-Lucian PREJBEANU
  • Publication number: 20220068339
    Abstract: A magnetic tunnel junction includes at least one free layer, at least one reference layer, and at least one tunnel barrier separating the free layer and the reference layer, wherein the free layer is an inhomogeneous granular layer including at least two grains, each grain of the at least two grains being sensibly magnetically decoupled from the other adjacent grains of the at least two grains.
    Type: Application
    Filed: August 24, 2021
    Publication date: March 3, 2022
    Inventors: Bernard DIENY, Marco MANSUETO, Ricardo SOUSA, Ioan-Lucian PREJBEANU, Liliana BUDA-PREJBEANU
  • Patent number: 10978234
    Abstract: A magnetic stack includes a first element including a ferromagnetic layer; a second element including a metal layer able to confer on the assembly formed by the first and the second elements a magnetic anisotropy perpendicular to the plane of the layers. The first element further includes a refractory metal material, the second element being arranged on the first element.
    Type: Grant
    Filed: February 15, 2019
    Date of Patent: April 13, 2021
    Assignees: COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, UNIVERSITÉ GRENOBLE ALPES, CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE (CNRS)
    Inventors: Jyotirmoy Chatterjee, Paulo Veloso Coelho, Bernard Dieny, Ricardo Sousa, Lucian Prejbeanu
  • Patent number: 10930841
    Abstract: A magnetic tunnel junction with out-of-plane magnetisation includes a storage layer; a reference layer; a tunnel barrier layer, the two magnetisation states of the storage layer being separated by an energy barrier, the magnetic tunnel junction having a thermal stability factor dependent on the energy barrier and on the temperature of use of the magnetic tunnel junction. The storage layer has a thickness comprised between 0.5 times and 8 times a characteristic dimension of a planar section of the tunnel junction; the composition and the thickness of the storage layer are chosen such that the absolute value of the derivative of the thermal stability factor compared to a characteristic dimension of a planar section of the tunnel junction is less than 10 nm?1.
    Type: Grant
    Filed: February 22, 2019
    Date of Patent: February 23, 2021
    Assignees: COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE (CNRS), INSTITUT POLYTECHNIQUE DE GRENOBLE
    Inventors: Nicolas Perrissin-Fabert, Bernard Dieny, Lucian Prejbeanu, Ricardo Sousa
  • Patent number: 10818329
    Abstract: A magnetic tunnel junction with out-of-plane magnetisation includes a storage layer; a reference layer; and a tunnel barrier layer. The two magnetisation states of the storage layer are separated by an energy barrier including a contribution due to the shape anisotropy of the storage layer and a contribution of interfacial origin for each interface of the storage layer. The storage layer has a thickness comprised between 0.8 and 8 times a characteristic dimension of a planar section of the tunnel junction. The contribution to the energy barrier due to the shape anisotropy of the storage layer is at least two times greater and preferably at least 4 times greater than the contributions to the energy barrier of interfacial origin.
    Type: Grant
    Filed: February 22, 2019
    Date of Patent: October 27, 2020
    Assignees: COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE (CNRS), INSTITUT POLYTECHNIQUE DE GRENOBLE
    Inventors: Nicolas Perrissin-Fabert, Bernard Dieny, Lucian Prejbeanu, Ricardo Sousa
  • Publication number: 20190326508
    Abstract: A magnetic tunnel junction with out-of-plane magnetisation includes a storage layer; a reference layer; a tunnel barrier layer, the two magnetisation states of the storage layer being separated by an energy barrier, the magnetic tunnel junction having a thermal stability factor dependent on the energy barrier and on the temperature of use of the magnetic tunnel junction. The storage layer has a thickness comprised between 0.5 times and 8 times a characteristic dimension of a planar section of the tunnel junction; the composition and the thickness of the storage layer are chosen such that the absolute value of the derivative of the thermal stability factor compared to a characteristic dimension of a planar section of the tunnel junction is less than 10 nm?1.
    Type: Application
    Filed: February 22, 2019
    Publication date: October 24, 2019
    Inventors: Nicolas PERRISSIN-FABERT, Bernard DIENY, Lucian PREJBEANU, Ricardo SOUSA
  • Publication number: 20190287591
    Abstract: A magnetic tunnel junction with out-of-plane magnetisation includes a storage layer; a reference layer; and a tunnel barrier layer. The two magnetisation states of the storage layer are separated by an energy barrier including a contribution due to the shape anisotropy of the storage layer and a contribution of interfacial origin for each interface of the storage layer. The storage layer has a thickness comprised between 0.8 and 8 times a characteristic dimension of a planar section of the tunnel junction. The contribution to the energy barrier due to the shape anisotropy of the storage layer is at least two times greater and preferably at least 4 times greater than the contributions to the energy barrier of interfacial origin.
    Type: Application
    Filed: February 22, 2019
    Publication date: September 19, 2019
    Inventors: Nicolas PERRISSIN-FABERT, Bernard DIENY, Lucian PREJBEANU, Ricardo SOUSA
  • Publication number: 20190252601
    Abstract: A magnetic stack includes a first element including a ferromagnetic layer; a second element including a metal layer able to confer on the assembly formed by the first and the second elements a magnetic anisotropy perpendicular to the plane of the layers. The first element further includes a refractory metal material, the second element being arranged on the first element.
    Type: Application
    Filed: February 15, 2019
    Publication date: August 15, 2019
    Inventors: Jyotirmoy CHATTERJEE, Paulo VELOSO COELHO, Bernard DIENY, Ricardo SOUSA, Lucian PREJBEANU
  • Patent number: 10236438
    Abstract: A mechanism is provided for a thermally assisted magnetoresistive random access memory device (TAS-MRAM). A storage layer has an anisotropic axis, in which the storage layer is configured to store a state in off axis positions and on axis positions. The off axis positions are not aligned with the anisotropic axis. A tunnel barrier is disposed on top of the storage layer. A ferromagnetic sense layer is disposed on top of the tunnel barrier.
    Type: Grant
    Filed: July 18, 2017
    Date of Patent: March 19, 2019
    Assignees: INTERNATIONAL BUSINESS MACHINES CORPORATION, CROCUS TECHNOLOGY SA
    Inventors: Anthony J. Annunziata, Lucian Prejbeanu, Philip L. Trouilloud, Daniel C. Worledge
  • Patent number: 10002973
    Abstract: The present disclosure concerns a method of fabricating a magnetic tunnel junction suitable for a magnetic random access memory (MRAM) cell and comprising a first ferromagnetic layer, a tunnel barrier layer, and a second ferromagnetic layer, comprising: forming the first ferromagnetic layer; forming the tunnel barrier layer; and forming the second ferromagnetic layer; wherein said forming the tunnel barrier layer comprises depositing a layer of metallic Mg; and oxidizing the deposited layer of metallic Mg such as to transform the metallic Mg into MgO; the step of forming the tunnel barrier layer being performed at least twice such that the tunnel barrier layer comprises at least two layers of MgO.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: June 19, 2018
    Assignee: CROCUS TECHNOLOGY SA
    Inventors: Ioan Lucian Prejbeanu, Celine Portemont, Clarisse Ducruet
  • Patent number: 9917247
    Abstract: A mechanism is provided for fabricating a thermally assisted magnetoresistive random access memory device. A bottom thermal barrier is formed on a bottom contact. A magnetic tunnel junction is formed on the bottom thermal barrier. The magnetic tunnel junction includes a top ferromagnetic layer formed on a tunnel barrier. The tunnel barrier is formed on a bottom ferromagnetic layer. A top thermal barrier is formed on the top ferromagnetic layer. A top contact is formed on the top thermal barrier. The top contact is reduced to a first diameter. The tunnel barrier and the bottom ferromagnetic layer each have a second diameter. The first diameter of the top contact is smaller than the second diameter.
    Type: Grant
    Filed: November 9, 2016
    Date of Patent: March 13, 2018
    Assignees: INTERNATIONAL BUSINESS MACHINES CORPORATION, CROCUS TECHNOLOGY SA
    Inventors: Anthony J. Annunziata, Lucian Prejbeanu, Philip L. Trouilloud, Daniel C. Worledge
  • Patent number: 9886989
    Abstract: The present disclosure concerns a magnetic random access memory (MRAM) cell suitable for performing a thermally assisted write operation or a spin torque transfer (STT) based write operation, comprising a magnetic tunnel junction comprising a top electrode; a tunnel barrier layer comprised between a first ferromagnetic layer having a first magnetization direction, and a second ferromagnetic layer having a second magnetization direction adjustable with respect to the first magnetization direction; a front-end layer; and a magnetic or metallic layer on which the second ferromagnetic layer is deposited; the second ferromagnetic layer being comprised between the front-end layer and the tunnel barrier layer and having a thickness comprised between about 0.5 nm and about 2 nm, such that magnetic tunnel junction has a magnetoresistance larger than about 100%. The MRAM cell disclosed herein has lower power consumption compared to conventional MRAM cells.
    Type: Grant
    Filed: January 18, 2012
    Date of Patent: February 6, 2018
    Assignee: CROCUS TECHNOLOGY SA
    Inventors: Clarisse Ducruet, Céline Portemont, Ioan Lucian Prejbeanu
  • Publication number: 20170317270
    Abstract: A mechanism is provided for a thermally assisted magnetoresistive random access memory device (TAS-MRAM). A storage layer has an anisotropic axis, in which the storage layer is configured to store a state in off axis positions and on axis positions. The off axis positions are not aligned with the anisotropic axis. A tunnel barrier is disposed on top of the storage layer. A ferromagnetic sense layer is disposed on top of the tunnel barrier.
    Type: Application
    Filed: July 18, 2017
    Publication date: November 2, 2017
    Inventors: Anthony J. Annunziata, Lucian Prejbeanu, Philip L. Trouilloud, Daniel C. Worledge
  • Patent number: 9786837
    Abstract: A mechanism is provided for a thermally assisted magnetoresistive random access memory device (TAS-MRAM). A storage layer has an anisotropic axis, in which the storage layer is configured to store a state in off axis positions and on axis positions. The off axis positions are not aligned with the anisotropic axis. A tunnel barrier is disposed on top of the storage layer. A ferromagnetic sense layer is disposed on top of the tunnel barrier.
    Type: Grant
    Filed: October 20, 2015
    Date of Patent: October 10, 2017
    Assignees: INTERNATIONAL BUSINESS MACHINES CORPORATION, CROCUS TECHNOLOGY SA
    Inventors: Anthony J. Annunziata, Lucian Prejbeanu, Philip L. Trouilloud, Daniel C. Worledge
  • Patent number: 9786836
    Abstract: A mechanism is provided for a thermally assisted magnetoresistive random access memory device (TAS-MRAM). A storage layer has an anisotropic axis, in which the storage layer is configured to store a state in off axis positions and on axis positions. The off axis positions are not aligned with the anisotropic axis. A tunnel barrier is disposed on top of the storage layer. A ferromagnetic sense layer is disposed on top of the tunnel barrier.
    Type: Grant
    Filed: October 20, 2015
    Date of Patent: October 10, 2017
    Assignees: INTERNATIONAL BUSINESS MACHINES CORPORATION, CROCUS TECHNOLOGY SA
    Inventors: Anthony J. Annunziata, Lucian Prejbeanu, Philip L. Trouilloud, Daniel C. Worledge
  • Patent number: 9754653
    Abstract: Method for writing and reading a plurality of data bits to a magnetic random access memory (MRAM) cell including a magnetic tunnel junction including a reference magnetic layer having a reference magnetization, a tunnel barrier layer, and a SAF storage magnetic layer including a first and second storage magnetization being coupled antiparallel through a storage coupling layer and freely orientable at a high temperature threshold. The method includes: heating the magnetic tunnel junction to the high temperature threshold; and applying a write magnetic field to orient the first and second storage magnetization; wherein the high temperature threshold includes one of a first or third high temperature threshold such as to orient the first storage magnetization respectively antiparallel or parallel to the second storage magnetization; or a second high temperature threshold such as to orient the first storage magnetization with an angle below 180° with respect to the second storage magnetization.
    Type: Grant
    Filed: October 11, 2013
    Date of Patent: September 5, 2017
    Assignee: CROCUS TECHNOLOGY SA
    Inventor: Ioan Lucian Prejbeanu
  • Patent number: 9728711
    Abstract: 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.
    Type: Grant
    Filed: April 11, 2014
    Date of Patent: August 8, 2017
    Assignee: CROCUS TECHNOLOGY SA
    Inventors: Sebastien Bandiera, Ioan Lucian Prejbeanu
  • Patent number: 9679624
    Abstract: A magnetic random access memory (MRAM) cell including a magnetic tunnel junction containing: a storage layer including at least one storage ferromagnetic layer, each storage ferromagnetic layer having a storage magnetization; an antiferromagnetic storage layer pinning the storage magnetization at a low threshold temperature and freeing them at a high temperature threshold; a reference layer; and a tunnel barrier layer between the reference layer and the storage layer. The magnetic tunnel junction also includes a free ferromagnetic layer having a free magnetization adapted to induce a magnetic stray field magnetically coupling the free ferromagnetic layer with the storage layer; such that the storage magnetization can be switched by the magnetic stray field when the magnetic tunnel junction is at the high temperature threshold. The disclosed MRAM cell has low power consumption.
    Type: Grant
    Filed: November 19, 2013
    Date of Patent: June 13, 2017
    Assignee: CROCUS TECHNOLOGY SA
    Inventors: Lucien Lombard, Ioan Lucian Prejbeanu
  • Publication number: 20170062701
    Abstract: A mechanism is provided for fabricating a thermally assisted magnetoresistive random access memory device. A bottom thermal barrier is formed on a bottom contact. A magnetic tunnel junction is formed on the bottom thermal barrier. The magnetic tunnel junction includes a top ferromagnetic layer formed on a tunnel barrier. The tunnel barrier is formed on a bottom ferromagnetic layer. A top thermal barrier is formed on the top ferromagnetic layer. A top contact is formed on the top thermal barrier. The top contact is reduced to a first diameter. The tunnel barrier and the bottom ferromagnetic layer each have a second diameter. The first diameter of the top contact is smaller than the second diameter.
    Type: Application
    Filed: November 9, 2016
    Publication date: March 2, 2017
    Inventors: Anthony J. Annunziata, Lucian Prejbeanu, Philip L. Trouilloud, Daniel C. Worledge