Patents by Inventor Bradley N. Engel

Bradley N. Engel 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).

  • Patent number: 8242776
    Abstract: A semiconductor process and apparatus provide a high-performance magnetic field sensor from two differential sensor configurations (201, 211) which require only two distinct pinning axes (206, 216), where each differential sensor (e.g., 201) is formed from a Wheatstone bridge structure with four unshielded MTJ sensors (202-205), each of which includes a magnetic field pulse generator (e.g., 414) for selectively applying a field pulse to stabilize or restore the easy axis magnetization of the sense layers (e.g., 411) to eliminate micromagnetic domain switches during measurements of small magnetic fields.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: August 14, 2012
    Assignee: Everspin Technologies, Inc.
    Inventors: Phillip G. Mather, Young Sir Chung, Bradley N. Engel
  • Patent number: 8237437
    Abstract: A fabrication process and apparatus provide a high-performance magnetic field sensor (200) from two differential sensor configurations (201, 211) which require only two distinct pinning axes (206, 216) which are formed from a single reference layer (60) that is etched into high aspect ratio shapes (62, 63) with their long axes drawn with different orientations so that, upon treating the reference layers with a properly aligned saturating field (90) and then removing the saturating field, the high aspect ratio patterns provide a shape anisotropy that forces the magnetization of each patterned shape (62, 63) to relax along its respective desired axis. Upon heating and cooling, the ferromagnetic film is pinned in the different desired directions.
    Type: Grant
    Filed: February 8, 2011
    Date of Patent: August 7, 2012
    Assignee: Everspin Technologies, Inc.
    Inventors: Bradley N Engel, Phillip G. Mather, Jon M. Slaughter
  • Patent number: 7965077
    Abstract: A fabrication process and apparatus provide a high-performance magnetic field sensor (200) from two differential sensor configurations (201, 211) which require only two distinct pinning axes (206, 216) which are formed from a single reference layer (60) that is etched into high aspect ratio shapes (62, 63) with their long axes drawn with different orientations so that, upon treating the reference layers with a properly aligned saturating field (90) and then removing the saturating field, the high aspect ratio patterns provide a shape anisotropy that forces the magnetization of each patterned shape (62, 63) to relax along its respective desired axis. Upon heating and cooling, the ferromagnetic film is pinned in the different desired directions.
    Type: Grant
    Filed: May 8, 2008
    Date of Patent: June 21, 2011
    Assignee: Everspin Technologies, Inc.
    Inventors: Bradley N. Engel, Phillip G. Mather, Jon M. Slaughter
  • Publication number: 20110121826
    Abstract: A fabrication process and apparatus provide a high-performance magnetic field sensor (200) from two differential sensor configurations (201, 211) which require only two distinct pinning axes (206, 216) which are formed from a single reference layer (60) that is etched into high aspect ratio shapes (62, 63) with their long axes drawn with different orientations so that, upon treating the reference layers with a properly aligned saturating field (90) and then removing the saturating field, the high aspect ratio patterns provide a shape anisotropy that forces the magnetization of each patterned shape (62, 63) to relax along its respective desired axis. Upon heating and cooling, the ferromagnetic film is pinned in the different desired directions.
    Type: Application
    Filed: February 8, 2011
    Publication date: May 26, 2011
    Applicant: EVERSPIN TECHNOLOGIES, INC.
    Inventors: Bradley N. ENGEL, Phillip G. MATHER, Jon M. SLAUGHTER
  • Patent number: 7635903
    Abstract: An oscillator includes at least one of: (i) a parallel array of resistors (420, 421, 422, 701, 801, 901, 902) or magnetoresistive contacts to a magnetoresistive film (120, 320); and (ii) a series array of resistors (620, 621, 702, 902) or magnetoresistive contacts to individualized areas of at least one magnetoresistive film.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: December 22, 2009
    Assignee: Everspin Technologies, Inc.
    Inventors: Frederick B. Mancoff, Bradley N. Engel, Nicholas D. Rizzo
  • Publication number: 20090279212
    Abstract: A fabrication process and apparatus provide a high-performance magnetic field sensor (200) from two differential sensor configurations (201, 211) which require only two distinct pinning axes (206, 216) which are formed from a single reference layer (60) that is etched into high aspect ratio shapes (62, 63) with their long axes drawn with different orientations so that, upon treating the reference layers with a properly aligned saturating field (90) and then removing the saturating field, the high aspect ratio patterns provide a shape anisotropy that forces the magnetization of each patterned shape (62, 63) to relax along its respective desired axis. Upon heating and cooling, the ferromagnetic film is pinned in the different desired directions.
    Type: Application
    Filed: May 8, 2008
    Publication date: November 12, 2009
    Inventors: Bradley N. Engel, Phillip G. Mather, Jon M. Slaughter
  • Patent number: 7602177
    Abstract: An apparatus (46, 416, 470) is provided for sensing physical parameters. The apparatus (46, 416, 470) comprises a magnetic tunnel junction (MTJ) (32, 432), first and second electrodes (36, 38, 426, 434), a magnetic field source (MFS) (34, 445, 476) whose magnetic field (35) overlaps the MTJ (32, 432) and a moveable magnetic cladding element (33, 448, 478) whose proximity (43, 462, 479, 479?) to the MFS (34, 445, 476) varies in response to an input to the sensor. The MFS (34, 445, 476) is located between the cladding element (33, 448, 478) and the MTJ (32, 432). Motion (41, 41?, 41-1, 464, 477) of the cladding element (33, 448, 478) relative to the MFS (34, 445, 476) in response to sensor input causes the magnetic field (35) at the MTJ (32, 432) to change, thereby changing the electrical properties of the MTJ (32, 432). A one-to-one correspondence (54) between the sensor input and the electrical properties of the MTJ (32, 432) is obtained.
    Type: Grant
    Filed: October 19, 2006
    Date of Patent: October 13, 2009
    Assignee: Everspin Technologies, Inc.
    Inventors: Brian R. Butcher, Kenneth H. Smith, Bradley N. Engel
  • Publication number: 20090243607
    Abstract: A semiconductor process and apparatus provide a high-performance magnetic field sensor from two differential sensor configurations (201, 211) which require only two distinct pinning axes (206, 216), where each differential sensor (e.g., 201) is formed from a Wheatstone bridge structure with four unshielded MTJ sensors (202-205), each of which includes a magnetic field pulse generator (e.g., 414) for selectively applying a field pulse to stabilize or restore the easy axis magnetization of the sense layers (e.g., 411) to eliminate micromagnetic domain switches during measurements of small magnetic fields.
    Type: Application
    Filed: March 26, 2008
    Publication date: October 1, 2009
    Inventors: Phillip G. Mather, Young Sir Chung, Bradley N. Engel
  • Patent number: 7547480
    Abstract: An integrated circuit device is provided which comprises a substrate, a conductive line configured to experience a pressure, and a magnetic tunnel junction (“MTJ”) core formed between the substrate and the current line. The conductive line is configured to move in response to the pressure, and carries a current which generates a magnetic field. The MTJ core has a resistance value which varies based on the magnetic field. The resistance of the MTJ core therefore varies with respect to changes in the pressure. The MTJ core is configured to produce an electrical output signal which varies as a function of the pressure.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: June 16, 2009
    Assignee: Everspin Technologies, Inc.
    Inventors: Young Sir Chung, Robert W. Baird, Bradley N. Engel
  • Patent number: 7541804
    Abstract: Methods and apparatus are provided for sensing physical parameters. The apparatus comprises a magnetic tunnel junction (MTJ) and a magnetic field source whose magnetic field overlaps the MTJ and whose proximity to the MTJ varies in response to an input to the sensor. The MTJ comprises first and second magnetic electrodes separated by a dielectric configured to permit significant tunneling conduction therebetween. The first magnetic electrode has its spin axis pinned and the second magnetic electrode has its spin axis free. The magnetic field source is oriented closer to the second magnetic electrode than the first magnetic electrode. The overall sensor dynamic range is extended by providing multiple electrically coupled sensors receiving the same input but with different individual response curves and desirably but not essentially formed on the same substrate.
    Type: Grant
    Filed: July 29, 2005
    Date of Patent: June 2, 2009
    Assignee: EverSpin Technologies, Inc.
    Inventors: Young Sir Chung, Robert W. Baird, Bradley N. Engel
  • Patent number: 7402529
    Abstract: A method of fabricating a cladding region for use in MRAM devices includes the formation of a conductive bit line proximate to a magnetoresistive memory device. The conductive bit line is immersed in a first bath containing dissolved ions of a first conductive material for a time sufficient to displacement plate a first barrier layer on the conductive line. The first barrier layer is then immersed in an electroless plating bath to form a flux concentrating layer on the first barrier layer. The flux concentrating layer is immersed in a second bath containing dissolved ions of a second conductive material for a time sufficient to displacement plate a second barrier layer on the flux concentrating layer.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: July 22, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Jaynal A. Molla, John D'Urso, Kelly Kyler, Bradley N. Engel, Gregory W. Grynkewich, Nicholas D. Rizzo
  • Patent number: 7329935
    Abstract: Low power magnetoresistive random access memory elements and methods for fabricating the same are provided. In one embodiment, a magnetoresistive random access device has an array of memory elements. Each element comprises a fixed magnetic portion, a tunnel barrier portion, and a free SAF structure. The array has a finite magnetic field programming window Hwin represented by the equation Hwin?(Hsat??sat)?(Hsw+?sw), where Hsw is a mean switching field for the array, Hsat is a mean saturation field for the array, and Hsw for each memory element is represented by the equation HSW??{square root over (HkHSAT)}, where Hk represents a total anisotropy and HSAT represents an anti-ferromagnetic coupling saturation field for the free SAF structure of each memory element. N is an integer greater than or equal to 1. Hk, HSAT, and N for each memory element are selected such that the array requires current to operate that is below a predetermined current value.
    Type: Grant
    Filed: October 16, 2006
    Date of Patent: February 12, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Nicholas D. Rizzo, Renu W. Dave, Bradley N. Engel, Jason A. Janesky, JiJun Sun
  • Patent number: 7262069
    Abstract: An integrated circuit device includes a magnetic random access memory (“MRAM”) architecture and at least one inductance element formed on the same substrate using the same fabrication process technology. The inductance element, which may be an inductor or a transformer, is formed at the same metal layer (or layers) as the program lines of the MRAM architecture. Any available metal layer in addition to the program line layers can be added to the inductance element to enhance its efficiency. The concurrent fabrication of the MRAM architecture and the inductance element facilitates an efficient and cost effective use of the physical space available over active circuit blocks of the substrate, resulting in three-dimensional integration.
    Type: Grant
    Filed: June 7, 2005
    Date of Patent: August 28, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Young Sir Chung, Robert W. Baird, Mark A. Durlam, Bradley N. Engel
  • Patent number: 7235408
    Abstract: A nearly balanced synthetic antiferromagnetic (SAF) structure that can be advantageously used in magnetoelectronic devices such as a magnetoresistive memory cell includes two ferromagnetic layers and an antiferromagnetic coupling layer separating the two ferromagnetic layers. The SAF free layer has weakly coupled regions formed in the antiferromagnetic coupling layer by a treatment such as annealing, layering of the antiferromagnetic coupling layer, or forming the antiferromagnetic coupling layer over a roughened surface of a ferromagnetic layer. The weakly coupled regions lower the flop field of the SAF free layer in comparison to untreated SAF free layers. The SAF flop is used during the write operation of such a structure and its reduction results in lower power consumption during write operations and correspondingly increased device performance.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: June 26, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Jason Allen Janesky, Bradley N. Engel, Nicholas D. Rizzo, Jon M Slaughter
  • Patent number: 7184300
    Abstract: A method to switch a scalable magnetoresistive memory cell including the steps of providing a magnetoresistive memory device sandwiched between a word line and a digit line so that current waveforms can be applied to the word and digit lines at various times to cause a magnetic field flux to rotate the effective magnetic moment vector of the device by approximately 180°. The magnetoresistive memory device includes N ferromagnetic layers that are anti-ferromagnetically coupled. N can be adjusted to change the magnetic switching volume of the device.
    Type: Grant
    Filed: January 9, 2003
    Date of Patent: February 27, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Anatoli Korkin, legal representative, Bradley N. Engel, Nicholas D. Rizzo, Mark F. Deherrera, Jason Allen Janesky, Leonid Savtchenko, deceased
  • Patent number: 7172904
    Abstract: The preferred embodiments of the present invention use MRAM technology to detect a shift in the magnetic switching field of a sensor. The shift in the magnetic switching field is caused by the presence of magnetic tagged beads. By measuring the magnitude of the shift in the magnetic field and correlating the magnitude of the shift to the presence of the target molecules, accurate measurements regarding the presence of the target molecules can be made.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: February 6, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Bradley N. Engel, Michael Ward
  • Patent number: 7149106
    Abstract: A magnetic random access memory (“MRAM”) device can be selectively written using spin-transfer reflection mode techniques. Selectivity of a designated MRAM cell within an MRAM array is achieved by the dependence of the spin-transfer switching current on the relative angle between the magnetizations of the polarizer element and the free magnetic element in the MRAM cell. The polarizer element has a variable magnetization that can be altered in response to the application of a current, e.g., a digit line current. When the magnetization of the polarizer element is in the natural default orientation, the data in the MRAM cell is preserved. When the magnetization of the polarizer element is switched, the data in the MRAM cell can be written in response to the application of a relatively low write current.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: December 12, 2006
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Frederick B. Mancoff, Bradley N. Engel, Nicholas D. Rizzo
  • Patent number: 7129098
    Abstract: Low power magnetoresistive random access memory elements and methods for fabricating the same are provided. In one embodiment, a magnetoresistive random access device has an array of memory elements. Each element comprises a fixed magnetic portion, a tunnel barrier portion, and a free SAF structure. The array has a finite magnetic field programming window Hwin represented by the equation Hwin?(Hsat?N?sat)?(Hsw+N?sw), where Hsw is a mean switching field for the array, Hsat is a mean saturation field for the array, and Hsw for each memory element is represented by the equation HSW??{square root over (HkHSAT)}, where Hk represents a total anisotropy and HSAT represents an anti-ferromagnetic coupling saturation field for the free SAF structure of each memory element. N is an integer greater than or equal to 1. Hk, HSAT, and N for each memory element are selected such that the array requires current to operate that is below a predetermined current value.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: October 31, 2006
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Nicholas D. Rizzo, Renu W. Dave, Bradley N. Engel, Jason A. Janesky, JiJun Sun
  • Patent number: 6967366
    Abstract: An array of multi-state, multi-layer magnetic memory devices (10) wherein each memory device comprises a nonmagnetic spacer region (22) and a free magnetic region (24) positioned adjacent to a surface of the nonmagnetic spacer region, the free magnetic region including a plurality of magnetic layers (36,34,38), wherein the magnetic layer (36) in the plurality of magnetic layers positioned adjacent to the surface of the nonmagnetic spacer region has a thickness substantially greater than a thickness of each of the magnetic layers (34,38) subsequently grown thereon wherein the thickness is chosen to improve the magnetic switching variation so that the magnetic switching field for each memory device in the array of memory devices is more uniform.
    Type: Grant
    Filed: August 25, 2003
    Date of Patent: November 22, 2005
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Jason A. Janesky, Bradley N. Engel, Jon M. Slaughter
  • Patent number: 6956763
    Abstract: A direct write is provided for a magnetoelectronics information device that includes producing a first magnetic field with a first field magnitude in proximity to the magnetoelectronics information device at a first time (t1). Once this first magnetic field with the first magnitude is produced, a second magnetic field with a second field magnitude is produced in proximity to the magnetoelectronics information device at a second time (t2). The first magnetic field is adjusted to provide a third magnitude at a third time (t3) that is less than the first field magnitude and greater than zero, and the second magnetic field is adjusted to provide a fourth field magnitude at a fourth time (t4) that is less than the second field magnitude. This direct write is used in conjunction with other direct writes and also in combination with toggle writes to write the MRAM element without an initial read.
    Type: Grant
    Filed: June 27, 2003
    Date of Patent: October 18, 2005
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Bengt J. Akerman, Mark F. Deherrera, Bradley N. Engel, Nicholas D. Rizzo