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: 8242776Abstract: 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: GrantFiled: March 26, 2008Date of Patent: August 14, 2012Assignee: Everspin Technologies, Inc.Inventors: Phillip G. Mather, Young Sir Chung, Bradley N. Engel
-
Patent number: 8237437Abstract: 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: GrantFiled: February 8, 2011Date of Patent: August 7, 2012Assignee: Everspin Technologies, Inc.Inventors: Bradley N Engel, Phillip G. Mather, Jon M. Slaughter
-
Patent number: 7965077Abstract: 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: GrantFiled: May 8, 2008Date of Patent: June 21, 2011Assignee: Everspin Technologies, Inc.Inventors: Bradley N. Engel, Phillip G. Mather, Jon M. Slaughter
-
Publication number: 20110121826Abstract: 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: ApplicationFiled: February 8, 2011Publication date: May 26, 2011Applicant: EVERSPIN TECHNOLOGIES, INC.Inventors: Bradley N. ENGEL, Phillip G. MATHER, Jon M. SLAUGHTER
-
Patent number: 7635903Abstract: 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: GrantFiled: September 13, 2005Date of Patent: December 22, 2009Assignee: Everspin Technologies, Inc.Inventors: Frederick B. Mancoff, Bradley N. Engel, Nicholas D. Rizzo
-
Publication number: 20090279212Abstract: 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: ApplicationFiled: May 8, 2008Publication date: November 12, 2009Inventors: Bradley N. Engel, Phillip G. Mather, Jon M. Slaughter
-
Patent number: 7602177Abstract: 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: GrantFiled: October 19, 2006Date of Patent: October 13, 2009Assignee: Everspin Technologies, Inc.Inventors: Brian R. Butcher, Kenneth H. Smith, Bradley N. Engel
-
Publication number: 20090243607Abstract: 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: ApplicationFiled: March 26, 2008Publication date: October 1, 2009Inventors: Phillip G. Mather, Young Sir Chung, Bradley N. Engel
-
Patent number: 7547480Abstract: 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: GrantFiled: October 28, 2005Date of Patent: June 16, 2009Assignee: Everspin Technologies, Inc.Inventors: Young Sir Chung, Robert W. Baird, Bradley N. Engel
-
Patent number: 7541804Abstract: 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: GrantFiled: July 29, 2005Date of Patent: June 2, 2009Assignee: EverSpin Technologies, Inc.Inventors: Young Sir Chung, Robert W. Baird, Bradley N. Engel
-
Patent number: 7402529Abstract: 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: GrantFiled: May 26, 2005Date of Patent: July 22, 2008Assignee: Freescale Semiconductor, Inc.Inventors: Jaynal A. Molla, John D'Urso, Kelly Kyler, Bradley N. Engel, Gregory W. Grynkewich, Nicholas D. Rizzo
-
Patent number: 7329935Abstract: 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: GrantFiled: October 16, 2006Date of Patent: February 12, 2008Assignee: Freescale Semiconductor, Inc.Inventors: Nicholas D. Rizzo, Renu W. Dave, Bradley N. Engel, Jason A. Janesky, JiJun Sun
-
Patent number: 7262069Abstract: 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: GrantFiled: June 7, 2005Date of Patent: August 28, 2007Assignee: Freescale Semiconductor, Inc.Inventors: Young Sir Chung, Robert W. Baird, Mark A. Durlam, Bradley N. Engel
-
Patent number: 7235408Abstract: 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: GrantFiled: March 9, 2005Date of Patent: June 26, 2007Assignee: Freescale Semiconductor, Inc.Inventors: Jason Allen Janesky, Bradley N. Engel, Nicholas D. Rizzo, Jon M Slaughter
-
Patent number: 7184300Abstract: 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: GrantFiled: January 9, 2003Date of Patent: February 27, 2007Assignee: 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: 7172904Abstract: 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: GrantFiled: July 31, 2002Date of Patent: February 6, 2007Assignee: Freescale Semiconductor, Inc.Inventors: Bradley N. Engel, Michael Ward
-
Patent number: 7149106Abstract: 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: GrantFiled: October 22, 2004Date of Patent: December 12, 2006Assignee: Freescale Semiconductor, Inc.Inventors: Frederick B. Mancoff, Bradley N. Engel, Nicholas D. Rizzo
-
Patent number: 7129098Abstract: 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: GrantFiled: November 24, 2004Date of Patent: October 31, 2006Assignee: Freescale Semiconductor, Inc.Inventors: Nicholas D. Rizzo, Renu W. Dave, Bradley N. Engel, Jason A. Janesky, JiJun Sun
-
Patent number: 6967366Abstract: 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: GrantFiled: August 25, 2003Date of Patent: November 22, 2005Assignee: Freescale Semiconductor, Inc.Inventors: Jason A. Janesky, Bradley N. Engel, Jon M. Slaughter
-
Patent number: 6956763Abstract: 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: GrantFiled: June 27, 2003Date of Patent: October 18, 2005Assignee: Freescale Semiconductor, Inc.Inventors: Bengt J. Akerman, Mark F. Deherrera, Bradley N. Engel, Nicholas D. Rizzo