Thin Film Magnetometers Patents (Class 324/249)
  • Patent number: 7923993
    Abstract: A rotation detection device includes a plurality of magnetic encoders of a ring shape arranged coaxially and having different numbers of magnetic poles, a plurality of magnetic sensors each operable to detect the magnetic field of the corresponding magnetic encoder and having a function of detecting positional information within a single magnetic pole of the corresponding magnetic encoder, a phase difference detector to determine the phase difference of magnetic field signals detected respectively by the magnetic sensors, and an angle calculator to calculate an absolute rotation angle of the magnetic encoders based on the detected phase difference.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: April 12, 2011
    Assignee: NTN Corporation
    Inventors: Toru Takahashi, Shintarou Ueno
  • Patent number: 7920975
    Abstract: Methods of detecting anomalies in ambient alternating current (AC) fields are provided. An exemplary embodiment of such a method includes the steps of placing an AC field sensor in an ambient AC field, generating a signal representative of the ambient AC field received by the sensor, and processing the signal to determine if the ambient AC field includes any anomalies. Various applications for the methods are also provided.
    Type: Grant
    Filed: August 20, 2007
    Date of Patent: April 5, 2011
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: David M. Hull, Stephen J. Vinci
  • Patent number: 7919961
    Abstract: The invention relates to a method for measuring the magnetic permeability of a magnetic material by measuring the magnetic interaction of an electromagnetic field with this material by using a measuring device including a measuring cell connected through a microwave frequency cable (13) to a vector network analyser (12), said method comprising steps for gauging/calibrating said measuring device, for determining corrective coefficients to be applied to the measurements obtained by means of this device, for verifying the non-drift of this device, these steps being carried out with the help of a reference sample, wherein a reference sample is used, comprising at least one inclusion which enables creation, in a given volume, of a local artificial permeability, each inclusion being achieved by combining at least one inductive component possibly associated with a combination of at last one capacitive and/or resistive and/or active component, the frequency response of the electromagnetic properties of each volume be
    Type: Grant
    Filed: October 20, 2006
    Date of Patent: April 5, 2011
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Marc Ledieu, Olivier Acher
  • Publication number: 20110062955
    Abstract: A multiferroic antenna and sensor where the sensor includes a multiferroic stack of multiple connected multiferroic layer-pairs, each multiferroic layer-pair comprising an alternating layer of a magnetostrictive material and a piezoelectric material bonded together enabling a high signal sensitivity, a magnetic field of an incident signal causing mechanical strain in the magnetostrictive material layers that strains adjacent piezoelectric material layers producing an electrical voltage in each multiferroic layer-pair proportional to the incident signal. An output of the multiferroic stack comprises the electrical voltage amplified proportional to a total number of multiple connected multiferroic layer-pairs in the multiferroic stack.
    Type: Application
    Filed: September 17, 2009
    Publication date: March 17, 2011
    Inventors: Robert J. Miller, William P. Geren, Stephen P. Hubbell
  • Patent number: 7906961
    Abstract: A magnetic field sensor arrangement (4) comprises a stacked arrangement (1) with a first magnetic field sensor body (20) and a second magnetic field sensor body (40). The first magnetic field sensor body (20) has a first main surface (21), on which is arranged a first magnetic field sensitive element (23), and a second main surface (22), which is approximately parallel to the first main surface (21). The second magnetic field sensor body (40) has similarly a first main surface (41), on which is arranged a second magnetic field sensitive element (43), and a second main surface (42), which is approximately parallel to the first main surface (41).
    Type: Grant
    Filed: December 19, 2006
    Date of Patent: March 15, 2011
    Assignee: austrianmicrosystems AG
    Inventors: Sari Abwa, Manfred Brandl, Josef Janisch
  • Patent number: 7898249
    Abstract: Methods of reorienting ferromagnetic layers of a plurality of magnetoresistive elements and structures formed by the methods. The plurality of magnetoresistive elements, preferably GMR multilayer elements, are manufactured and arranged on a planar substrate. The method effectively allows selective orientation and reorientation of distinct ferromagnetic layers of a subset of the magnetoresistive elements on the substrate. The methods make either use of subsequent annealing processes making use of magnetic fields pointing in different directions. Prior to application of a subsequent annealing process, a complimentary subset of magnetoresistive elements is effectively shielded by selective deposition of a soft-magnetic shielding layer. Alternatively, a single annealing process can be performed when an externally applied magnetic field is locally modified by soft-magnetic structures, such as fluxguides.
    Type: Grant
    Filed: July 16, 2008
    Date of Patent: March 1, 2011
    Assignee: International Business Machines Corporation
    Inventors: Johannes Paul, Rolf Schaefer
  • Publication number: 20100294978
    Abstract: The present invention provides a metal/insulator nanogranular material including: ferromagnetic particles having a composition represented by the formula (1) (Fe1?xCox)100?z(B1?ySiy)z??(1) in which x, y and z each satisfy 0?x?1, 0?y?1, and 0<z?20; and an insulating matrix constituted of an Mg—F compound, the insulating matrix being filled to surround the ferromagnetic particles.
    Type: Application
    Filed: May 18, 2010
    Publication date: November 25, 2010
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Seiichi NAGATA, Shigenobu KOYAMA, Sanji KANIE
  • Publication number: 20100271017
    Abstract: A fluxgate magnetic field sensor including an excitation current conductor (4) and a layer of saturable magnetic material cladding (6) having a plurality of feed-through channels (16) extending between opposed faces of the cladding layer, the excitation current conductor weaving through a plurality of said feed-through channels.
    Type: Application
    Filed: December 12, 2007
    Publication date: October 28, 2010
    Applicant: Liaisons Electroniques-Mecaniques Lem SA
    Inventor: Wolfram Teppan
  • Patent number: 7808236
    Abstract: Apparatus and method for harvesting energy from the environment and/or other external sources and converting it to useful electrical energy. The harvester does not contain a permanent magnet or other local field source but instead relies on the earth's magnetic field of another source of a magnetic field that is external to the sensing device. One advantage of these new harvesters is that they can be made smaller and lighter than energy harvesters that contain a magnet and/or an inertial mass.
    Type: Grant
    Filed: January 11, 2007
    Date of Patent: October 5, 2010
    Assignee: Ferro Solutions, Inc.
    Inventors: Jiankang Huang, Robert C. O'Handley, David C. Bono
  • Patent number: 7786726
    Abstract: A magnetic sensor that is inexpensive and suppresses changes in offset voltage caused by wear. The magnetic sensor includes magnetoresistance elements having electrical resistances that change in accordance with magnetism changes. The magnetic sensor detects magnetism based on changes in the electrical resistances. The magnetoresistance elements are covered by a protective film. Part of the protective film is etched and eliminated to form a recess.
    Type: Grant
    Filed: August 1, 2006
    Date of Patent: August 31, 2010
    Assignee: Kabushiki Kaisha Tokai Rika Denki Seisakusho
    Inventors: Yoichi Ishizaki, Katsuya Kogiso, Toru Minagawa, Fumihiro Suzuki
  • Patent number: 7782049
    Abstract: A magnetic device comprises a magnetic element, a first magnetic field application device, and a second magnetic field application device. The first and second magnetic field applying means are disposed on mutually opposite sides of the magnetic element. The magnetic element is, for example, an element in which a soft magnetic film is formed in a meandering shape on a nonmagnetic substrate. The first and second magnetic field application device create a magnetic field in one direction from the first magnetic field application device toward the second magnetic field application device. The bias magnetic field in one direction is thereby applied to the entire soft magnetic film in the magnetic element disposed between the first and second magnetic field application device.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: August 24, 2010
    Assignee: Fujikura Ltd.
    Inventors: Kazuhisa Itoi, Katsubumi Nagasu, Takuya Aizawa, Osamu Nakao, Shigekazu Kawai
  • Patent number: 7772841
    Abstract: A magnetic device comprises a magnetic element, a first magnetic field applying means, and a second magnetic field applying means. The first and second magnetic field applying means are disposed on mutually opposite sides of the magnetic element. The magnetic element is, for example, an element in which a soft magnetic film is formed in a meandering shape on a nonmagnetic substrate. The first and second magnetic field applying means create a magnetic field in one direction from the first magnetic field applying means toward the second magnetic field applying means. The bias magnetic field in one direction is thereby applied to the entire soft magnetic film in the magnetic element disposed between the first and second magnetic field applying means.
    Type: Grant
    Filed: January 13, 2010
    Date of Patent: August 10, 2010
    Assignee: Fujikura Ltd.
    Inventors: Kazuhisa Itoi, Katsubumi Nagasu, Takuya Aizawa, Osamu Nakao, Shigekazu Kawai
  • Publication number: 20100148771
    Abstract: This invention provides a magnetic sensor element that can detect a detection target substance with high accuracy. The magnetic sensor element includes a multi-magnetic domain structure in which a plurality of magnetic domains extend in a row in one direction and in which the magnetic domains that are adjoining have easy magnetization axes in opposite directions to each other. The multi-magnetic domain structure has a surface region. Within the surface region, when counting from one end of the multi-magnetic domain structure, affinities for a magnetic particle or a substance that can be immobilized on the magnetic particle are mutually different at a first surface portion located at a boundary between a (2n?1)th (n is a natural number) magnetic domain and a (2n)th magnetic domain and a second surface portion located at a boundary between the (2n)th magnetic domain and a (2n+1)th magnetic domain.
    Type: Application
    Filed: June 23, 2008
    Publication date: June 17, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Miki Ueda
  • Patent number: 7737687
    Abstract: A fluxgate sensor includes a magnetic core including CoNbZr, an excitation coil, and a magnetic field sensing coil. The fluxgate sensor can use CoNbZr. A low coercivity and high magnetic permeability can be obtained.
    Type: Grant
    Filed: October 18, 2006
    Date of Patent: June 15, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Kyung-won Na, Jingli Yuan, Sang-on Choi
  • Patent number: 7723984
    Abstract: The present invention provides a current sensor of smaller and simpler configuration, capable of measuring a current to be detected with high precision and stability. A magnetic sensor includes: an element substrate including a magnetoresistive element, the magnetoresistive element having a pinned layer with a magnetization pinned to a direction, an intermediate layer, and a free layer whose magnetization direction changes according to an external magnetic field; and a magnetic sheet attached on one side of the element substrate so as to apply a bias magnetic field to the magnetoresistive element.
    Type: Grant
    Filed: September 26, 2006
    Date of Patent: May 25, 2010
    Assignee: TDK Corporation
    Inventors: Shigeru Shoji, Masato Takahashi
  • Patent number: 7710708
    Abstract: A two-axis geomagnetic sensor is disclosed. The two-axis geomagnetic sensor includes a first geomagnetic sensor part including a first wafer and a first geomagnetic sensor on a surface of the first wafer; and a second geomagnetic sensor part including a second wafer and a second geomagnetic sensor on a surface of the second wafer. The first and second geomagnetic sensor parts are bonded to each other, in which the first and second geomagnetic sensors positioned in an orthogonal relation to each other. Accordingly, an occupancy area of the geomagnetic sensor can be reduced. Further, the geomagnetic sensor on each axe can have the same magnetic material properties, and alignment deviation cannot be generated.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: May 4, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hae-seok Park, Joo-ho Lee, Hyung Choi, Kyoung-won Na
  • Patent number: 7683612
    Abstract: The thin film magnetic sensor comprising a GMR film having a Giant Magneto-Resistance effect; and thin film yokes formed of a soft magnetic material connected electrically to both ends of the GMR film; wherein the thin film yoke has a high sensitivity portion with a demagnetizing factor of NL in a magnetic sensitive direction, and a low sensitivity portion with a demagnetizing factor of NH(>NL) in the magnetic sensitive direction, the low sensitivity portion being connected electrically in series with the high sensitivity portion.
    Type: Grant
    Filed: December 30, 2008
    Date of Patent: March 23, 2010
    Assignee: Daido Steel Co., Ltd.
    Inventor: Shigenobu Koyama
  • Publication number: 20100045282
    Abstract: Relating to a thin film lamination and a thin film magnetic sensor using the thin film lamination and a method for manufacturing the thin film lamination that realizes a thin film conducting layer having high electron mobility and sheet resistance as an InAsSb operating layer. A thin film lamination is provided which is characterized by having an AlxIn1-xSb mixed crystal layer formed on a substrate, and an InAsxSb1-x (0<x?1) thin film conducting layer directly formed on the AlxIn1-xSb layer, in which the AlxIn1-xSb mixed crystal layer is a layer that exhibits higher resistance than the InAsxSb1-x thin film conducting layer or exhibits insulation or p-type conductivity, and its band gap is greater than the InAsxSb1-x thin film conducting layer, and the a lattice mismatch is +1.3% to ?0.8%.
    Type: Application
    Filed: November 29, 2007
    Publication date: February 25, 2010
    Inventors: Ichiro Shibasaki, Hirotaka Geka, Atsushi Okamoto
  • Publication number: 20100007343
    Abstract: A magnetic field effect sensor system having giant magneto-impedance elements. The elements may be elongated strips, and in proximity to and parallel with one another, and connected in series with connections or electrodes. The elements may have a regular shape without turns. They may have a single- or multi-layer structure. Some of the layers in the elements may contain a soft magnetic material, for instance, which form a closed loop for magnetic flux around a non-magnetic conductor.
    Type: Application
    Filed: July 10, 2008
    Publication date: January 14, 2010
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventors: Xinhui Mao, HuanBin Fang
  • Patent number: 7646196
    Abstract: Provided is a current sensor capable of detecting an induced magnetic field by a current to be detected with higher precision. The first and second modules are provided on facing surfaces of integrated substrates, respectively, with spacers in between. Each of the first and second modules includes an element substrate, and an MR element layer. On each of the MR elements layers, provided is an MR element having a stacked structure including a pinned layer, a nonmagnetic intermediate layer, and a free layer whose magnetization direction changes according to the induced magnetic field and which exhibits an anisotropic field in a direction different from that of the magnetization of the pinned layer. The stacked structures of the MR elements are provided in a same layer level.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: January 12, 2010
    Assignee: TDK Corporation
    Inventor: Shigeru Shoji
  • Patent number: 7629789
    Abstract: A magnetoresistive assembly includes at least a first and a second magnetoresistive element formed on a common substrate, the at least first magnetoresistive element comprising a first pinned ferromagnetic layer being magnetized in a first direction, the at least second magnetoresistive element comprising a second pinned ferromagnetic layer being magnetized in a second direction different than the first direction.
    Type: Grant
    Filed: July 16, 2008
    Date of Patent: December 8, 2009
    Assignee: International Business Machines Corporation
    Inventors: Johannes Paul, Rolf Schaefer
  • Patent number: 7615995
    Abstract: A thin-film device for detecting the variation of intensity of physical quantities, in particular a magnetic field, in a continuous way, comprises an electrical circuit including one or more sensitive elements, which are designed to vary their own electrical resistance as a function of the intensity of a physical quantity to be detected. One or more of the sensitive elements comprise at least one nanoconstriction, and the nanoconstriction comprises at least two pads made of magnetic material, associated to which are respective magnetizations oriented in directions substantially opposite to one another and connected through a nanochannel. The nanochannel is able to set up a domain wall that determines the electrical resistance of the nanoconstriction as a function of the position, with respect to the nanochannel, of the domain wall formed in the sensor device.
    Type: Grant
    Filed: August 30, 2006
    Date of Patent: November 10, 2009
    Assignee: C.R.F. Società Consortile per Azioni
    Inventors: Daniele Pullini, Gianfranco Innocenti, Piermario Repetto, Antonio Ruotolo
  • Patent number: 7602176
    Abstract: In order to provide a magneto-resistive angle sensor (100) comprising a sensor device for detecting an angle (?) of an external magnetic field relative to a reference axis of the sensor device, which allows measurement of the angle (?) without the measurement result being affected by manufacturing errors, it is proposed that the sensor device comprises a flat AMR layer (14, 15) with one electrical contact (K0) for applying a current (I) and a plurality of electrical contacts (Ki) for measuring a flow of current through the AMR layer (14,15).
    Type: Grant
    Filed: December 20, 2004
    Date of Patent: October 13, 2009
    Assignee: NXP B.V.
    Inventor: Stefan Butzmann
  • 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: 7592803
    Abstract: An AMR gear tooth rotation sensor and a method for utilizing it are disclosed. These facilitate easy manufacture of the device without sacrificing either high sensitivity or high signal output. This is achieved by forming individual sensing elements out of AMR stripes and then connecting four such sensing elements as a Wheatstone bridge. The latter is attached to a permanent magnet that provides a bias field whose value rises and falls as wheel teeth and valleys (respectively) move past the rotation sensor.
    Type: Grant
    Filed: June 23, 2008
    Date of Patent: September 22, 2009
    Assignee: MagIC Technologies, Inc.
    Inventors: Yimin Guo, Grace Gorman
  • Publication number: 20090212770
    Abstract: The thin film magnetic sensor comprising a GMR film having a Giant Magneto-Resistance effect; and thin film yokes formed of a soft magnetic material connected electrically to both ends of the GMR film; wherein the thin film yoke has a high sensitivity portion with a demagnetizing factor of NL in a magnetic sensitive direction, and a low sensitivity portion with a demagnetizing factor of NH(>NL) in the magnetic sensitive direction, the low sensitivity portion being connected electrically in series with the high sensitivity portion.
    Type: Application
    Filed: December 30, 2008
    Publication date: August 27, 2009
    Applicant: DAIDO STEEL CO., LTD.
    Inventor: Shigenobu KOYAMA
  • Patent number: 7557571
    Abstract: A fluxgate sensor is integrated in a semiconductor substrate. The fluxgate sensor has two bar type soft magnetic cores, or a rectangular-ring type soft magnetic core to form a closed magnetic path on the semiconductor substrate, with an excitation coil formed of a metal layer either of the united structure winding the two bar-type cores or two longer sides of the rectangular-ring type core altogether and substantially in a number ‘8’ pattern, or of a separated structure winding the two bar type cores or two longer sides of the rectangular-ring type core, respectively, in a number ‘8’ pattern. Also, a pick-up coil is formed on the two bar-type cores or two longer sides of the rectangular-ring type core, either of the united structure winding the two bar-type cores or two longer sides of the rectangular-type core altogether in a solenoid pattern, or of the separated structure winding the two bar type cores or two longer sides of the rectangular-ring type core, respectively, in a solenoid pattern.
    Type: Grant
    Filed: September 12, 2002
    Date of Patent: July 7, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Won-youl Choi, Kyung-won Na, Sang-on Choi
  • Patent number: 7514804
    Abstract: A method of harvesting vibrational energy is provided. This method involves generating a high magnetic flux density field within a current induction conductor such as an induction coil. The high magnetic flux density field is generated between two same pole magnets. The high magnetic flux density field may be displaced relative to the current induction conductor with vibrational energy. These displacements then cause the current induction conductor to be energized. The two same pole magnets are mounted between piezoelectric transducer (PZT) materials. These PZT materials generate an electric potential when the PZT materials are subject to the mechanical stresses of the vibrational energy. The electrical energy translated from the vibrational energy through both the energized current induction conductor and stress PZT materials may then be used to power a power circuitry or be stored for later use.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: April 7, 2009
    Assignee: Lockheed Martin Corporation
    Inventor: Sheng T. Wang
  • Patent number: 7508203
    Abstract: A magnetic field detector having a reference magnetoresistive element and a magnetic field detecting magnetoresistive element. The reference magnetoresistive element and the magnetic field detecting magnetoresistive element each has a stack structure including an antiferromagnetic layer, a fixed layer of a ferromagnetic material with the direction of magnetization fixed by the antiferromagnetic layer, a nonmagnetic layer, and a free layer of a ferromagnetic material with the direction of magnetization adapted to be changed by an external magnetic field. The reference magnetoresistive element is such that the direction of magnetization of the fixed layer and the direction of magnetization of the free layer in the nonmagnetic field are parallel or antiparallel to each other, and the magnetic field detecting magnetoresistive element is such that the direction of magnetization of the fixed layer and the direction of magnetization of the free layer in the nonmagnetic field are different from each other.
    Type: Grant
    Filed: April 4, 2008
    Date of Patent: March 24, 2009
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takashi Takenaga, Hiroshi Kobayashi, Takeharu Kuroiwa, Sadeh Beysen, Taisuke Furukawa
  • Patent number: 7498805
    Abstract: A magnetoresistive layer system, in an environment of a magnetoresistive layer stack that works particularly on the basis of the GMR effect or the AMR effect, a layer array being provided which generates a magnetic field which acts upon the magnetoresistive layer stack, and the layer array having at least one hard magnetic layer and at least one soft magnetic layer. Furthermore, a sensor element, particularly for the detection of magnetic fields with respect to their strength and/or direction, having such a layer system.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: March 3, 2009
    Assignee: Robert Bosch GmbH
    Inventors: Henrik Siegle, Maik Rabe, Ulrich May
  • Patent number: 7498802
    Abstract: An inductive sensor includes an inductor comprising conductive loops and at least one hinge mechanically coupling the loops. Operation of the hinge changes the position of the loops and causes a change in the inductance of the sensor. A sensor material may be oriented with respect to the loops so that a dimensional change of the sensor material operates the hinge and causes the change in the position of the loops.
    Type: Grant
    Filed: July 10, 2006
    Date of Patent: March 3, 2009
    Assignee: 3M Innovative Properties Company
    Inventor: Kenichi Takahata
  • Publication number: 20090052484
    Abstract: A Magneto-Optoelectronic Device MOD (10) includes a magnetic sensing device (12), such as a magnetoresistive device or a magnetic tunnel junction device, that is combined with a semiconductor light emitter (14), such as a LED or a laser diode, to create a compact integrated device where changes in an ambient magnetic field are expressed as changes in an optical beam intensity emanating from the MOD. Using the MOD (10) the magnetic field related information can be transmitted by a light wave over very large distances through some medium (34), for example, through free space and/or through an optical fiber.
    Type: Application
    Filed: October 16, 2008
    Publication date: February 26, 2009
    Inventor: Arto V. Nurmikko
  • Patent number: 7474094
    Abstract: Methods of reorienting ferromagnetic layers of a plurality of magnetoresistive elements and structures formed by the methods. The plurality of magnetoresistive elements, preferably GMR multilayer elements, are manufactured and arranged on a planar substrate. The method effectively allows selective orientation and reorientation of distinct ferromagnetic layers of a subset of the magnetoresistive elements on the substrate. The methods make either use of subsequent annealing processes making use of magnetic fields pointing in different directions. Prior to application of a subsequent annealing process, a complimentary subset of magnetoresistive elements is effectively shielded by selective deposition of a soft-magnetic shielding layer. Alternatively, a single annealing process can be performed when an externally applied magnetic field is locally modified by soft-magnetic structures, such as fluxguides.
    Type: Grant
    Filed: August 30, 2005
    Date of Patent: January 6, 2009
    Assignee: International Business Machines Corporation
    Inventors: Johannes Paul, Rolf Schaefer
  • Patent number: 7459906
    Abstract: To detect a magnetic flux density of a magnetic field applied from an outside, a semiconductor magnetic sensor of the present invention includes: a transistor (MP101) formed on a side of one, side of a hall element (100), for driving the hall element (100), the transistor (MP101) having a drain connected to a terminal (C101) formed on the one side; a transistor (MP102) formed on the side of the one side and having a drain connected to a terminal (C102) formed on the one side; a transistor (MN101) formed on a side of another side opposite to the one side and having a drain connected to a terminal (C103) formed on the another side; a transistor (MN102) formed on the side of the another side and having a drain connected to a terminal (C104) formed on the another side.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: December 2, 2008
    Assignee: Seiko Instruments Inc.
    Inventor: Tomoki Hikichi
  • Patent number: 7446524
    Abstract: A ferromagnetic thin-film based magnetic field detection system used for detecting the presence of selected molecular species. A magnetic field sensor supported on a substrate has a binding molecule layer positioned on a side thereof capable of selectively binding to the selected molecular species held on a magnetic particle. The magnetic field sensor can be substantially covered by an electrical insulating layer having a recess therein adjacent to the sensor in which the binding molecule layer is provided. A thin-film channel structure to the sensor is supported on the substrate that can be accompanied by a reservoir structure, and an electrical interconnection conductor is supported on the substrate at least in part between the sensor and the substrate, and is electrically connected to the sensor. The magnetic field sensor can be provided in a bridge circuit, and can be formed by a number of interconnected individual sensors.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: November 4, 2008
    Assignee: NVE Corporation
    Inventor: Mark C. Tondra
  • Patent number: 7425824
    Abstract: A magnetic sensor, system and method include a magnet located proximate to a target comprising a plurality of teeth and a plurality of slots formed therebetween. An integrated circuit is located on a side of the magnet wherein the integrated circuit comprises a plurality of magnetoresistive bridge components. The integrated circuit and the magnet are configured into a sensor package, such that the magnetoresistive bridge components enable the detection of a target tooth when one half of the plurality of magnetoresistive bridge components come into proximity with an edge of a tooth before that of another half of the magnetoresistive bridge components as the tooth and an associated slot thereof pass by the sensor package.
    Type: Grant
    Filed: June 20, 2005
    Date of Patent: September 16, 2008
    Assignee: Honeywell International Inc.
    Inventor: Nicholas F. Busch
  • Patent number: 7414399
    Abstract: The invention relates to a fluxgate micromagnetometer implemented in thin layers, fitted with at least one excitation coil with an arrangement and a structure that bring improvements particularly in terms of the magnetometer footprint, reduction in the “offsets” of measurements taken by the magnetometer, common mode rejection.
    Type: Grant
    Filed: April 30, 2007
    Date of Patent: August 19, 2008
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Elisabeth Delevoye, Christian Jeandey
  • Patent number: 7411391
    Abstract: A magnetic-field-measuring probe includes at least one magnetoresistive or magnetoinductive sensor which is sensitive to the magnetic field along a privileged measurement axis. The probe includes: at least two magnetoresistive or magnetoinductive sensors (14, 16) which are rigidly connected to one another in a position such that the privileged measurement axes thereof are parallel and offset in relation to one another in a direction that is transverse to the privileged measurement axes; and output terminals specific to each magnetoresistive or magnetoinductive sensor, in order to supply a signal that is representative of the magnetic field measured by each sensor along the privileged measurement axis thereof.
    Type: Grant
    Filed: October 8, 2004
    Date of Patent: August 12, 2008
    Assignee: Centre National d'Etudes Spatiales
    Inventors: Romain Desplats, Olivier Crepel, Félix Beaudoin, Philippe Perdu
  • Patent number: 7407596
    Abstract: A fluxgate sensor is integrated in a printed circuit board. The fluxgate sensor has two bar-type (or rectangular-ring shaped) soft magnetic cores to form a closed magnetic path on a printed circuit board and an excitation coil in the form of a metal film is wound around the two bar-type soft magnetic cores either in a united structure that winds the two bar-type soft magnetic cores altogether, or in a separated structure that winds the two bar-type soft magnetic cores respectively, both in a pattern of number ‘8’. A pick-up coil is mounted on the excitation coil, either winding the two bars altogether, or respectively, in a solenoid pattern. The fluxgate sensor integrated in the printed circuit board can be mass-produced at a cheap manufacturing cost. The fluxgate sensor also can be made compact-sized, and at the same time, is capable of forming a closed-magnetic path.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: August 5, 2008
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Won-youl Choi, Byeong-cheon Koh, Kyung-won Na, Sang-on Choi, Myung-sam Kang, Keon-yang Park
  • Patent number: 7408343
    Abstract: A magnetoresistive sensor system includes a plurality of chip carriers, such that each integrated circuit among the plurality of chip carriers is associated with a respective magnetoresistive sensing components. A plurality of magnetoresistive sensing components can be arranged in an array, wherein each magnetoresistive component among the plurality of magnetoresistive components is associated with a respective integrated circuit among the plurality of chip carriers and wherein the plurality of magnetoresistive sensing components comprises sensing components that are spaced irregular from one another in order to optimize the performance of the array and meet requirements of a particular magnetoresistive sensing application.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: August 5, 2008
    Assignee: Honeywell International Inc.
    Inventors: Anthony M. Dmytriw, Michael J. Latoria, Lamar F. Ricks
  • Patent number: 7405559
    Abstract: The present invention is an electrical circuit for a sensor designed to detect external magnetic fields. The circuit is composed of a stable voltage reference source, connected to a low frequency amplifier where the operating point of the amplifier depends on the voltage reference source that is biased for maximum allowable voltage swings of the amplifier. A GMI fiber is connected to the low frequency amplifier and to a crystal oscillator that generates a square wave excitation signal with which to excite the GMI fiber. A decoupling network connected to the amplifier allows stable excitation of the GMI fiber by separating the direct current paths of the amplifier from the excitation signal. When the GMI fiber is excited by the square wave signal the GMI fiber impedance varies with impressed magnetic fields, which in turn varies the output voltage of the amplifier.
    Type: Grant
    Filed: June 26, 2006
    Date of Patent: July 29, 2008
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: James D. Hagerty
  • Patent number: 7400137
    Abstract: The present invention provides a magnetic sensor suitable for high resolution and having high reliability by achieving stable output even at the occurrence of variations in a gap between a magnetic medium and the magnetic sensor, and a magnetic encoder using the magnetic sensor. The present invention uses a magnetoresistive element having magnetoresistive properties that satisfy the inequation, H10?50<H50?90, where H10?50 represents a magnetic field required for a resistance change from ?R×10% to ?R×50% with respect to a maximum amount of resistance change ?R on a magnetoresitance effect curve, and H50?90 represents a magnetic field required for a resistance change from ?R×50% to ?R×90%.
    Type: Grant
    Filed: August 6, 2007
    Date of Patent: July 15, 2008
    Assignee: Hitachi Metals, Ltd.
    Inventors: Kenichi Meguro, Hiroyuki Hoshiya, Kazuhiro Nakamoto, Yasuyuki Okada, Yasunori Abe
  • Patent number: 7400143
    Abstract: A magnetic bias film 9 includes a magnetic bias magnet 11 that has magnetic layers and generates a magnetic field within a plane perpendicular to a lamination direction of the magnetic layers, which is manufactured in the shape of substantially a rectangular prism having a long side, a short side, and a thickness (in the lamination direction) in order of decreasing lengths. A ratio of the long side with respect to the short side of the magnetic bias magnet 11 in length is in a range of 5 to 200.
    Type: Grant
    Filed: September 6, 2004
    Date of Patent: July 15, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nobukazu Hayashi, Kazuhiro Onaka, Yukio Nakao, Masataka Tagawa, Kouji Nabetani, Masako Yamaguchi
  • Patent number: 7394247
    Abstract: The invention discloses a sensor for 360-degree magnetic field angle measurement. It comprises multiple GMR (or MTJ) stripes with identical geometries except for their orientations. These are used as the building blocks for a pair of Wheatstone bridges that signal the direction of magnetization of their environment. The design greatly enhances sensitivity within GMR stripes and does not require an additional Hall sensor in order to cover the full 360 degree measurement range.
    Type: Grant
    Filed: July 26, 2007
    Date of Patent: July 1, 2008
    Assignee: Magic Technologies, Inc.
    Inventors: Yimin Guo, Grace Gorman, Po-Kang Wang
  • Patent number: 7394249
    Abstract: Disclosed is a printed circuit board with a weak magnetic field sensor according to the present invention, which includes a substrate having first excitation circuits and first detection circuits formed on both sides thereof. First laminates are layered on both sides of the substrate, and have soft magnetic cores with a predetermined shape formed thereon. Second laminates are layered on the first laminates, and have second excitation circuits and second detection circuits, connected through via holes to the first excitation circuits and first detection circuits, respectively, so that the first and second excitation circuits and first and second detection circuits are wound around the soft magnetic cores, formed thereon. The soft magnetic cores each include a magnetic core and non-magnetic metal layers formed on both sides of the magnetic core.
    Type: Grant
    Filed: October 14, 2004
    Date of Patent: July 1, 2008
    Assignee: Samsung Electro-Mechanics Co., Ltd
    Inventors: Myung-Sam Kang, Chang-Sup Ryu, Won-Cheol Bae, Jae-Kul Lee, Doo-Hwan Lee
  • Patent number: 7394248
    Abstract: The process margin for the manufacture of devices formed from multi-element MTJ or GMR devices has been widened by providing a method and structure to reset the magnetization directions of all pinned layers simultaneously so that their directions of magnetization become evenly distributed. This has the effect of minimizing non-linearity and hysteresis in these devices during their subsequent operation.
    Type: Grant
    Filed: August 2, 2007
    Date of Patent: July 1, 2008
    Assignee: Magic Technologies, Inc.
    Inventors: Yimin Guo, Grace Gorman
  • Patent number: 7385394
    Abstract: A sensor component used to measure a magnetic field strength is disclosed. In one embodiment, the sensor component contains a plurality of leads and a sensor semiconductor chip, which measures the magnetic field strength. The sensor semiconductor chip has pads on its active upper side. These pads are connected electrically to the leads. The sensor component also contains a magnet, which is attached to the leads. The sensor semiconductor chip is arranged on an upper side of the magnet. The sensor component also has a first mold compound which shares a common boundary with the sensor semiconductor chip and surrounds the sensor semiconductor chip, the magnet and parts of the lead.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: June 10, 2008
    Assignee: Infineon Technologies AG
    Inventors: Albert Auburger, Jochen Dangelmaier, Alfred Gottlieb, Martin Petz, Uwe Schindler, Horst Theuss
  • Patent number: 7382123
    Abstract: A micro-machining method of manufacturing a micro fluxgate sensor manufactured having an amorphous magnetic core includes forming lower coils of an excitation coil and a magnetic field detecting coil on a wafer, depositing a first insulating layer on the lower coils and forming an amorphous magnetic core, depositing a second insulating layer on the amorphous magnetic core and forming upper coils connected to the lower coils to complete the excitation coil and the magnetic field detecting coil, and covering the excitation coil and the magnetic field detecting coil with a protective film, and etching the protective film to expose a portion of the excitation coil and magnetic field detecting coil, thereby forming a pad.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: June 3, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Kyung-won Na, Sang-on Choi, Hae-seok Park, Dong-sik Shim
  • Patent number: 7375516
    Abstract: A magnetic field detector having a reference magnetoresistive element and a magnetic field detecting magnetoresistive element. The reference magnetoresistive element and the magnetic field detecting magnetoresistive element each has a stack structure including an antiferromagnetic layer, a fixed layer of a ferromagnetic material with the direction of magnetization fixed by the antiferromagnetic layer, a nonmagnetic layer, and a free layer of a ferromagnetic material with the direction of magnetization adapted to be changed by an external magnetic field. The reference magnetoresistive element is such that the direction of magnetization of the fixed layer and the direction of magnetization of the free layer in the nonmagnetic field are parallel or antiparallel to each other, and the magnetic field detecting magnetoresistive element is such that the direction of magnetization of the fixed layer and the direction of magnetization of the free layer in the nonmagnetic field are different from each other.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: May 20, 2008
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takashi Takenaga, Hiroshi Kobayashi, Takeharu Kuroiwa, Sadeh Beysen, Taisuke Furukawa
  • Patent number: 7375515
    Abstract: A magnetic sensor circuit supplying an excitation current to an MI device, and having a detection signal supplied thereto corresponding to a magnetic field intensity from the MI device based on the excitation current. The magnetic sensor circuit includes a pulse current supplying circuit supplying a pulse current to the MI device; a sample-and-hold circuit maintaining an approximately peak value of the detection signal and outputting a hold signal; and a temperature compensation part compensating temperature characteristics of the magnetic sensor circuit with respect to the hold signal. The sample-and-hold circuit may include a switching circuit and a holding capacitor. The switching circuit may have an opening/closing control signal supplied thereto based on timing of the pulse current.
    Type: Grant
    Filed: December 23, 2005
    Date of Patent: May 20, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuya Omagari, Masaki Mori