Patents by Inventor Jeffrey Childress

Jeffrey Childress 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: 20240027551
    Abstract: Magnetoresistive element including a reference layer having a fixed reference magnetization, a sense layer having a free sense magnetization and a tunnel barrier layer between the reference layer and the sense layer; the magnetoresistive element being configured to measure an external magnetic field oriented substantially perpendicular to the plane of the layers. The reference magnetization being oriented substantially perpendicular to the plane of the reference layer. The sense magnetization including a vortex configuration in the absence of an external magnetic field, the vortex configuration being substantially parallel to the plane of the sense layer and having a vortex core magnetization along an out-of-plane axis substantially perpendicular to the plane of the sense layer.
    Type: Application
    Filed: December 9, 2021
    Publication date: January 25, 2024
    Inventors: Jeffrey Childress, Nikita Strelkov
  • Publication number: 20240019509
    Abstract: A magnetoresistive element for a magnetic sensor, the magnetoresistive element including a tunnel barrier layer between a reference layer having a fixed reference magnetization and a sense layer having a free sense magnetization, wherein the sense magnetization includes a stable vortex configuration. The magnetoresistive element further includes a reference pinning layer in contact with the reference layer and pining the reference magnetization by exchange-bias at a first blocking temperature. The magnetoresistive element further includes a sense pinning layer in contact with the sense layer and pining the sense magnetization by exchange-bias at a second blocking temperature lower that the first blocking temperature. Additionally, a method for manufacturing the magnetoresistive element.
    Type: Application
    Filed: October 28, 2021
    Publication date: January 18, 2024
    Inventors: Jeffrey Childress, Nikita Strelkov, Andrey Timopheev
  • Publication number: 20230296703
    Abstract: A magnetoresistive element for a 2D magnetic sensor, the magnetoresistive element including a tunnel barrier layer included between a reference layer having a reference magnetization and a sense layer having a sense magnetization. The sense layer includes a sense synthetic antiferromagnetic structure including a first sense sublayer in contact with the tunnel barrier layer and separated from a second sense sublayer by a first non-magnetic spacer layer such that the first sense sublayer is antiferromagnetically coupled to the second sense sublayer. The sense layer is configured such that a sense magnetic ratio ?M defined as: ? M = M s F M 2 t F M 2 ? M s F M 1 t F M 1 M s F M 2 t F M 2 + M s F M 1 t F M 1 wherein MSFM1 and MSFM2 are the spontaneous magnetizations of the first and second sense sublayers and tFM1 and tFM2 are the thicknesses of the first and second sense sublayers; and wherein the sense magnetic ratio is between 0.1 and 0.25.
    Type: Application
    Filed: September 14, 2021
    Publication date: September 21, 2023
    Inventors: Andrey Timopheev, Nikita Strelkov, Jeffrey Childress
  • Publication number: 20230292624
    Abstract: A magnetic sensor including a plurality of magnetoresistive elements; each magnetoresistive element including a ferromagnetic layer having a magnetization that is orientable at or above a threshold temperature; the magnetic sensor further includes a plasmonic structure destined to be irradiated by electromagnetic radiation and including a spatially periodic plasmonic array of metallic structures. The period of the plasmonic array and the lateral dimension of the metallic structures are adjusted to obtain plasmon resonance of the plasmonic structure for a given wavelength of the electromagnetic radiation. The plasmonic array is arranged in the magnetic sensor such as to heat the first ferromagnetic layer at or above the threshold temperature, from the enhanced absorption of the electromagnetic radiation by plasmon resonance. The present disclosure further concerns a system including the sensor and an emitting device configured to emit electromagnetic radiation.
    Type: Application
    Filed: May 27, 2021
    Publication date: September 14, 2023
    Inventors: Andrey Timopheev, Nikita Strelkov, Jeffrey Childress
  • Publication number: 20230213597
    Abstract: Magnetic angular sensor element destined to sense an external magnetic field, including a magnetic tunnel junction containing a ferromagnetic pinned layer having a pinned magnetization, a ferromagnetic sensing layer, and a tunnel magnetoresistance barrier layer; the ferromagnetic sensing layer including a first sensing layer being in direct contact with the barrier layer and having a first sensing magnetization, a second sensing layer having a second sense magnetization, and a metallic spacer between the first sensing layer and the second sensing layer; wherein the metallic spacer is configured to provide an antiferromagnetic coupling between the first sensing magnetization and the second sensing magnetization such that the first sensing magnetization is oriented substantially antiparallel to the second sensing magnetization; the second sensing magnetization being larger than the first sensing magnetization, such that the second sensing magnetization is oriented in accordance with the direction of the externa
    Type: Application
    Filed: May 10, 2021
    Publication date: July 6, 2023
    Inventors: Andrey Timopheev, Jeffrey Childress, Nikita Strelkov
  • Publication number: 20230127582
    Abstract: A magnetoresistive element for a two-dimensional magnetic field sensor, including: a ferromagnetic reference layer having a fixed reference magnetization, a ferromagnetic sense layer having a sense magnetization that can be freely oriented relative to the reference magnetization in the presence of an external magnetic field, and a tunnel barrier layer between the reference and sense ferromagnetic layers; the reference layer including a reference coupling layer between a reference pinned layer and a reference coupled layer; the reference coupled layer including a first coupled sublayer in contact with the reference coupling layer, a second coupled sublayer, a third coupled sublayer and a insert layer between the second and third coupled sublayers; the insert layer comprising a transition metal and has a thickness between about 0.1 and about 0.5 nm, and the thickness of the reference coupled layer is between about 1 nm and about 5 nm.
    Type: Application
    Filed: March 2, 2021
    Publication date: April 27, 2023
    Inventors: Clarisse Ducruet, Léa Cuchet, Jeffrey Childress
  • Publication number: 20230066027
    Abstract: A magnetoresistive sensor element including: a reference layer having a pinned reference magnetization; a sense layer having a free sense magnetization comprising a stable vortex configuration reversibly movable in accordance to an external magnetic field to be measured; a tunnel barrier layer between the reference layer and the sense layer; wherein the sense layer includes a first ferromagnetic sense portion in contact with the tunnel barrier layer and a second ferromagnetic sense portion in contact with the first ferromagnetic sense portion; the second ferromagnetic sense portion including a dilution element in a proportion such that a temperature dependence of a magnetic susceptibility of the sense layer substantially compensates a temperature dependence of a tunnel magnetoresistance of the magnetoresistive sensor element. Also, a method for manufacturing the magnetoresistive sensor element.
    Type: Application
    Filed: January 29, 2021
    Publication date: March 2, 2023
    Inventors: Léa Cuchet, Andrey Timopheev, Jeffrey Childress
  • Publication number: 20220308133
    Abstract: Magnetic field sensor for sensing a two-dimensional external magnetic field, including a magnetic tunnel junction including a reference layer having a fixed reference magnetization, a sense ferromagnetic layer having a sense magnetization, and a tunnel barrier layer between the sense and reference ferromagnetic layers; the sense ferromagnetic layer including a first sense ferromagnetic layer in contact with the tunnel barrier layer, a second sense ferromagnetic layer, and a first non-magnetic layer between the first and second sense ferromagnetic layers; the second sense ferromagnetic layer includes a plurality of multilayer element, each multilayer element including a second non-magnetic layer between two second ferromagnetic sense layers; and wherein the second sense ferromagnetic layer has a thickness equal or less than 12 nm.
    Type: Application
    Filed: June 26, 2020
    Publication date: September 29, 2022
    Inventors: Léa Cuchet, Clarisse Ducruet, Jeffrey Childress
  • Patent number: 11397863
    Abstract: The present disclosure concerns a magnetic reader (MR) sensor device for reading magnetic stripes, the MR sensor device comprising a substrate provided on a wafer, a back-end-of-line (BEOL) interconnect layer and a plurality of magneto-resistive sensor elements embedded within the BEOL interconnect layer; the MR sensor device comprising a protective layer having a Vickers hardness of at least 3 GPa. The present disclosure further concerns a method for manufacturing the MR sensor device. The MR sensor device can be brought close to the surface to the magnetic stripe so that the magnetic stripe can be read with an increased resolution.
    Type: Grant
    Filed: December 23, 2019
    Date of Patent: July 26, 2022
    Assignee: CROCUS TECHNOLOGY SA
    Inventors: Ali Alaoui, Jeffrey Childress, Hakan Ates Gurcan
  • Patent number: 11017828
    Abstract: An apparatus for generating a magnetic field including permanent magnets arranged in a plane, each magnet being spatially separated along the plane from the adjacent magnet by a predetermined spacing, each magnet having a magnetic polarity opposed to the polarity of the adjacent magnet such that a magnetic field of adjacent magnets is oriented substantially perpendicular to the plane and in opposite directions, each magnet being spatially separated in the plane from the adjacent magnet by a nonmagnetic material. A method for programming a magnetic device or sensor device using the apparatus is also described.
    Type: Grant
    Filed: June 25, 2018
    Date of Patent: May 25, 2021
    Assignee: CROCUS TECHNOLOGY SA
    Inventors: Jeremy Alvarez-Herault, Lucien Lombard, Quentin Stainer, Jeffrey Childress
  • Publication number: 20200243127
    Abstract: An apparatus for generating a magnetic field including permanent magnets arranged in a plane, each magnet being spatially separated along the plane from the adjacent magnet by a predetermined spacing, each magnet having a magnetic polarity opposed to the polarity of the adjacent magnet such that a magnetic field of adjacent magnets is oriented substantially perpendicular to the plane and in opposite directions, each magnet being spatially separated in the plane from the adjacent magnet by a nonmagnetic material. A method for programming a magnetic device or sensor device using the apparatus is also described.
    Type: Application
    Filed: June 25, 2018
    Publication date: July 30, 2020
    Inventors: Jeremy Alvarez-Herault, Lucien Lombard, Quentin Stainer, Jeffrey Childress
  • Publication number: 20200202082
    Abstract: The present disclosure concerns a magnetic reader (MR)sensor device for reading magnetic stripes, the MR sensor device comprising a substrate provided on a wafer, a back-end-of-line (BEOL) interconnect layer and a plurality of magneto-resistive sensor elements embedded within the BEOL interconnect layer; the MR sensor device comprising a protective layer having a Vickers hardness of at least 3 GPa. The present disclosure further concerns a method for manufacturing the MR sensor device. The MR sensor device can be brought close to the surface to the magnetic stripe so that the magnetic stripe can be read with an increased resolution.
    Type: Application
    Filed: December 23, 2019
    Publication date: June 25, 2020
    Inventors: Ali Alaoui, Jeffrey Childress, Ates Gurcan
  • Patent number: 10663537
    Abstract: A magnetic sensor cell including a magnetic tunnel junction including a reference layer having a reference magnetization oriented substantially 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. The sense layer includes an intrinsic anisotropy substantially perpendicular to the plane of the sense layer such that the sense magnetization is orientable between an initial direction perpendicular to the plane of the sense layer and a direction parallel to the plane of the sense layer; the intrinsic anisotropy having in anisotropy field being above 150 Oe.
    Type: Grant
    Filed: April 7, 2017
    Date of Patent: May 26, 2020
    Assignee: CROCUS TECHNOLOGY SA
    Inventors: Jeffrey Childress, Romain Foissac, Kenneth MacKay
  • Publication number: 20180292473
    Abstract: A magnetic sensor cell including a magnetic tunnel junction including a reference layer having a reference magnetization oriented substantially 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. The sense layer includes an intrinsic anisotropy substantially perpendicular to the plane of the sense layer such that the sense magnetization is orientable between an initial direction perpendicular to the plane of the sense layer and a direction parallel to the plane of the sense layer; the intrinsic anisotropy having in anisotropy field being above 150 Oe.
    Type: Application
    Filed: April 7, 2017
    Publication date: October 11, 2018
    Inventors: Jeffrey Childress, Romain Foissac, Kenneth MacKay
  • Publication number: 20080074807
    Abstract: A magnetoresistive sensor having a pinned layer that includes a first magnetic layer (AP1) a second magnetic layer (AP2) and an antiparallel coupling layer sandwiched between the AP1 and AP2 layers. The AP1 layer is adjacent to a layer of antiferromagnetic material (AFM layer) and is constructed so as to have a long spin diffusion length. The long spin diffusion length of the AP1 layer minimizes the negative GMR contribution of the AP1 layer, thereby increasing the overall GMR effect of the sensor.
    Type: Application
    Filed: November 21, 2007
    Publication date: March 27, 2008
    Inventors: Matthew Carey, Shekar Chandrashekariaih, Stefan Maat, Jeffrey Childress
  • Publication number: 20080042779
    Abstract: A microwave bandstop filter having a magnetic strip formed over dielectric material. The magnetic resonant frequency is controlled by an induced magnetic anisotropy in the magnetic strip of the microwave bandstop filter. The magnetic anisotropy field is induced by an anisotropic surface texture formed on the surface of the magnetic strip itself, or formed on an underlying layer. Alternatively, the anisotropic surface texture could be formed on both an underlying layer and on the magnetic strip itself. This induced magnetic anisotropy field allows the resonant frequency of the microwave filter to be controlled over a wide frequency range and make high frequency operation possible without reliance on the application of an externally applied magnetic field.
    Type: Application
    Filed: August 27, 2007
    Publication date: February 21, 2008
    Inventors: Matthew Carey, Jeffrey Childress, Stefan Maat
  • Publication number: 20070281079
    Abstract: A magnetoresistive sensor having a magnetically stable free layer fabricated from a material having a positive magnetostriction such as a Co—Fe—B alloy. Although the free layer is fabricated from a material that has a positive magnetostriction, which would ordinarily make the free layer unstable, the magnetization of the free layer remains stable because of an induced magnetic anisotropy that has an easy axis of magnetization oriented parallel to the Air-bearing Surface (ABS). This magnetic anisotropy of the free layer is induced by an anisotropic texturing of the surface of the free layer. The resulting anisotropic surface texture is produced by an ion milling process that utilizes an ion beam directed at an acute angle relative to the normal to the surface of the wafer whereon the sensor is fabricated while the wafer is held on a stationary chuck.
    Type: Application
    Filed: April 19, 2007
    Publication date: December 6, 2007
    Inventors: Matthew Carey, Jeffrey Childress, Stefan Maat, James Nix
  • Publication number: 20070253119
    Abstract: A current-perpendicular-to-the-plane (CPP) magnetoresistive sensor has an antiparallel free (APF) structure as the free layer and a specific direction for the applied bias or sense current. The (APF) structure has a first free ferromagnetic (FL1), a second free ferromagnetic layer (FL2), and an antiparallel (AP) coupling (APC) layer that couples FL1 and FL2 together antiferromagnetically with the result that FL1 and FL2 have substantially antiparallel magnetization directions and rotate together in the presence of a magnetic field. The thicknesses of FL1 and FL2 are chosen to obtain the desired net free layer magnetic moment/area for the sensor, and the thickness of FL1 is preferably chosen to be greater than the spin-diffusion length of the electrons in the FL1 material to maximize the bulk spin-dependent scattering of electrons and thus maximize the sensor signal.
    Type: Application
    Filed: April 27, 2006
    Publication date: November 1, 2007
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B. V.
    Inventors: Matthew Carey, Jeffrey Childress, Stefan Maat, Neil Smith
  • Publication number: 20070188937
    Abstract: A current-perpendicular-to-the-plane spin-valve (CPP-SV) magnetoresistive sensor has a high-resistivity amorphous ferromagnetic alloy in the free layer and/or the pinned layer. The sensor may have an antiparallel (AP)-pinned structure, in which case the AP2 layer may be formed of the high-resistivity amorphous ferromagnetic alloy. The amorphous alloy is an alloy of one or more elements selected from Co, Fe and Ni, and at least one nonmagnetic element X. The additive element or elements is present in an amount that renders the otherwise crystalline alloy amorphous and thus substantially increases the electrical resistivity of the layer. As a result the resistance of the active region of the sensor is increased. The amount of additive element or elements is chosen to be sufficient to render the alloy amorphous but not high enough to substantially reduce the magnetic moment M or bulk electron scattering parameter ?.
    Type: Application
    Filed: February 16, 2006
    Publication date: August 16, 2007
    Inventors: Matthew Carey, Jeffrey Childress, Stefan Maat
  • Publication number: 20070171581
    Abstract: Formation of the magnetic sensor layers of a magnetic sensor are separated into at least two depositions to reduce the dimension of the sensor. The free layer portion of the sensor is deposited at a different process step than the pinned layer portion. The top of the free layer stack can be a tunnel barrier, the free layer, or part of the free layer. The free layer stack also may contain an in-stack bias layer. The longitudinal bias layer may be patterned in a separate processing step, which allows the stack containing the free layer to be effectively thinner and allow smaller track width dimensions.
    Type: Application
    Filed: January 20, 2006
    Publication date: July 26, 2007
    Inventors: Jeffrey Childress, Robert Fontana, Jeffrey Lille