Patents by Inventor Mark B. Johnson

Mark B. Johnson 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: 7173419
    Abstract: Magnetic field sensors, each generating an electrical output signal in proportion to the local magnetic field, are lithographically fabricated on a semiconductor substrate with a small spatial separation. The lateral dimension of the sensors and the separation length are the order of the minimum lithographic feature size. Comparing the electrical signals of the sensors results in a measurement of the local magnetic field gradient. Large field gradients, that vary on a small spatial scale, may be associated small magnetic structures such as microscopic magnetic particles. Detection of a field gradient can be used to infer the presence of a magnetic particle.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: February 6, 2007
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Mark B Johnson, Michael M Miller
  • Patent number: 7126331
    Abstract: Magnetic field sensors, each generating an electrical output signal in proportion to the local magnetic field, are lithographically fabricated on a semiconductor substrate with a small spatial separation. The lateral dimension of the sensors and the separation length are the order of the minimum lithographic feature size. Comparing the electrical signals of the sensors results in a measurement of the local magnetic field gradient. Large field gradients, that vary on a small spatial scale, may be associated small magnetic structures such as microscopic magnetic particles. Detection of a field gradient can be used to infer the presence of a magnetic particle.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: October 24, 2006
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Mark B. Johnson, Michael Miller
  • Patent number: 7068535
    Abstract: A new nonvolatile hybrid memory cell is provided. The cell is comprised of a magnetic spin storage element and one or two semiconductor FET isolation elements. The magnetic spin storage element is an electron spin-based memory element situated on a silicon based substrate and includes a first ferromagnetic layer with a changeable magnetization state, and a second ferromagnetic layer with a non-changeable magnetization state. A current of spin polarized electrons has a magnitude which can be varied so that a data value can be stored in the memory element by varying a relative orientation of the two ferromagnetic layers.
    Type: Grant
    Filed: October 8, 2004
    Date of Patent: June 27, 2006
    Inventor: Mark B. Johnson
  • Patent number: 7064542
    Abstract: A modified hybrid Hall effect device is provided which is the combination of a conventional Hall effect device and a second Hall effect device having a Hall plate coupled to a ferromagnetic layer. The hybrid Hall effect device can be used to determine the independent magnetic field vector components comprising a vector magnetic field, such as for determining the x and the z components of a magnetic field, or for measuring the total magnitude of a vector magnetic field of any orientation. The modified Hall Effect device can be adapted for use as a magnetic field sensor for the detection of macroscopic objects that have associated magnetic fields, or for microscopic objects that have been tagged by microscopic magnetic particles. In one specific form, a plurality of hybrid Hall devices are electrically connected together to form an array in which a plurality of rows of hybrid Hall devices are electrically coupled to each other along a current axis, and the array is used for the detection of microscopic objects.
    Type: Grant
    Filed: July 1, 2005
    Date of Patent: June 20, 2006
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Mark B. Johnson, Michael Miller, Brian Bennett
  • Patent number: 7064976
    Abstract: A method of operating a spin based memory cell stacked architecture is provided. The cells are comprised of magnetic spin storage elements stacked on top of each other on a silicon substrate, as well as one or two semiconductor FET isolation elements.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: June 20, 2006
    Assignee: Spin Op Corporation
    Inventor: Mark B. Johnson
  • Patent number: 7050329
    Abstract: A new nonvolatile hybrid memory cell is provided. The cell is comprised of a magnetic spin storage element which is written using inductive write lines. The magnetic spin storage element is an electron spin-based memory element situated on a silicon based substrate and includes a first ferromagnetic layer with a changeable magnetization state, and a second ferromagnetic layer with a non-changeable magnetization state. A current of spin polarized electrons has a magnitude which can be varied so that a data value can be stored in the memory element by varying a relative orientation of the two ferromagnetic layers using a magnetic field imposed by the inductive write lines.
    Type: Grant
    Filed: October 8, 2004
    Date of Patent: May 23, 2006
    Inventor: Mark B. Johnson
  • Patent number: 7020013
    Abstract: A hybrid magnetic-semiconductor structure can be used as a magnetic field sensor. The hybrid device uses ferromagnetic materials for implementing a variable spin resistance. An external magnetic field can change the magnetization state of the device by orienting the magnetization of the ferromagnetic layers to be parallel or antiparallel, thus changing the resistance of the device to a current of spin polarized electrons.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: March 28, 2006
    Inventor: Mark B. Johnson
  • Patent number: 7016223
    Abstract: The magnetization state of a ferromagnetic layer can be set to correspond to different values of a data item to be stored in a hybrid memory device. The magnetization state is non-volatile, and a write circuit can be coupled to the ferromagnetic layer to reset or change the magnetization state to a different value. The write circuit uses a pair of inductively coupled write wires in each row and column, which are each given a signal with an amplitude approximately ½ of that required to change the state of the ferromagnetic layer.
    Type: Grant
    Filed: May 2, 2005
    Date of Patent: March 21, 2006
    Inventor: Mark B. Johnson
  • Patent number: 7009875
    Abstract: Ferromagnetic elements for use with spin memories, logic devices and processing circuits include a geometry incorporating an asymmetry about one axis and in some instances one or more curved sections. Magnetic memory elements can be set out in an array such that convex and concave portions are also optimally arranged about magnetization axes.
    Type: Grant
    Filed: May 19, 2005
    Date of Patent: March 7, 2006
    Inventor: Mark B. Johnson
  • Patent number: 6975533
    Abstract: A nonvolatile hybrid memory cell is provided which includes magnetic and semiconductor components. The cell uses a thin film stack of ferromagnetic layers situated over a silicon substrate to store data in the form of variable impedance to a spin polarized current. The cell data is isolated by semiconductor isolation elements.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: December 13, 2005
    Inventor: Mark B. Johnson
  • Patent number: 6958930
    Abstract: A new magnetic spin device can be used as a memory element or logic gate, such as an OR, AND, NOT, NOR and NAND gate. The state of the magnetic spin device is set inductively. A magnetic spin transistor/gate can be operated with current gain. Furthermore, inductive coupling permits the linking of multiple spin transistors and spin transistor gates to perform combinational tasks. A half adder embodiment is specifically described, and other logic gates and combinations of half adders can be constructed to perform arithmetic functions as part of a microprocessor.
    Type: Grant
    Filed: May 24, 2004
    Date of Patent: October 25, 2005
    Inventor: Mark B. Johnson
  • Patent number: 6917198
    Abstract: A modified hybrid Hall effect device is provided which is the combination of a conventional Hall effect device and a second Hall effect device having a Hall plate coupled to a ferromagnetic layer. The hybrid Hall effect device can be used to determine the independent magnetic field vector components comprising a vector magnetic field, such as for determining the {circumflex over (x)} and the {circumflex over (z)} components of a magnetic field, or for measuring the total magnitude of a vector magnetic field of any orientation. The modified Hall Effect device can be adapted for use as a magnetic field sensor for the detection of macroscopic objects that have associated magnetic fields, or for microscopic objects that have been tagged by microscopic magnetic particles.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: July 12, 2005
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Mark B. Johnson, Michael Miller, Brian Bennett
  • Patent number: 6888746
    Abstract: The magnetization state of a ferromagnetic layer can be set to correspond to different values of a data item to be stored in a hybrid memory device. The magnetization state is non-volatile, and a write circuit can be coupled to the ferromagnetic layer to reset or change the magnetization state to a different value. The write circuit uses a pair of inductively coupled write wires in each row and column, which are each given a signal with an amplitude approximately ½ of that required to change the state of the ferromagnetic layer.
    Type: Grant
    Filed: May 24, 2004
    Date of Patent: May 3, 2005
    Inventor: Mark B. Johnson
  • Patent number: 6873545
    Abstract: A hybrid magnetic—semiconductor structure can be used as a memory element for the nonvolatile storage of digital information, as well as in other environments, including for example logic applications for performing digital combinational tasks, or a magnetic field sensor. The hybrid device uses ferromagnetic materials for implementing a variable spin resistance. The ferromagnetic layers are fabricated to permit the device to have two stable magnetization states, parallel and antiparallel. In the “on” state the device has two settable, stable resistance states determined by the relative orientation of the magnetizations of the ferromagnetic layers. An external magnetic field can change the magnetization state of the device by orienting the magnetization of the ferromagnetic layers to be parallel or antiparallel, thus changing the resistance of the device to a current of spin polarized electrons.
    Type: Grant
    Filed: May 24, 2004
    Date of Patent: March 29, 2005
    Inventor: Mark B. Johnson
  • Patent number: 6870761
    Abstract: A new nonvolatile hybrid memory cell stacked architecture is provided. The cells are comprised of magnetic spin storage elements stacked on top of each other on a silicon substrate, as well as one or two semiconductor FET isolation elements.
    Type: Grant
    Filed: February 10, 2004
    Date of Patent: March 22, 2005
    Inventor: Mark B. Johnson
  • Publication number: 20040251506
    Abstract: Hall Effect devices, memory devices, and Hall Effect device readout voltage increasing method. A hall effect device includes a conductive film layer capable an electrical current, a ferromagnetic layer having a configurable orientation and configured to cover a portion of the conductive film layer such that fringe magnetic fields can be generated by an edge portion of the ferromagnetic layer, a high permeability magnetic layer disposed below the conductive film layer. The fringe magnetic fields are drawn toward the high permeability magnetic layer such that the magnetic fields pass though the conductive film layer to enable closure of the magnetic fields.
    Type: Application
    Filed: June 10, 2003
    Publication date: December 16, 2004
    Inventors: Mark B. Johnson, Gary A. Prinz
  • Publication number: 20040217756
    Abstract: A modified hybrid Hall effect device is provided which is the combination of a conventional Hall effect device and a second Hall effect device having a Hall plate coupled to a ferromagnetic layer. The hybrid Hall effect device can be used to determine the independent magnetic field vector components comprising a vector magnetic field, such as for determining the {circumflex over (x)} and the {circumflex over (z)} components of a magnetic field, or for measuring the total magnitude of a vector magnetic field of any orientation. The modified Hall Effect device can be adapted for use as a magnetic field sensor for the detection of macroscopic objects that have associated magnetic fields, or for microscopic objects that have been tagged by microscopic magnetic particles.
    Type: Application
    Filed: May 21, 2004
    Publication date: November 4, 2004
    Inventors: Mark B. Johnson, Michael Miller, Brian Bennett
  • Publication number: 20040218443
    Abstract: A hybrid magnetic-semiconductor structure can be used as a memory element for the nonvolatile storage of digital information, as well as in other environments, including for example logic applications for performing digital combinational tasks, or a magnetic field sensor. The hybrid device uses ferromagnetic materials for implementing a variable spin resistance. The ferromagnetic layers are fabricated to permit the device to have two stable magnetization states, parallel and antiparallel. In the “on” state the device has two settable, stable resistance states determined by the relative orientation of the magnetizations of the ferromagnetic layers. An external magnetic field can change the magnetization state of the device by orienting the magnetization of the ferromagnetic layers to be parallel or antiparallel, thus changing the resistance of the device to a current of spin polarized electrons.
    Type: Application
    Filed: May 24, 2004
    Publication date: November 4, 2004
    Inventor: Mark B. Johnson
  • Publication number: 20040213041
    Abstract: A hybrid memory device combines a ferromagnetic layer and a Hall Effect device. The ferromagnetic layer is magnetically coupled to a portion of a Hall plate, and when such plate is appropriately biased, a Hall Effect signal can be generated whose value is directly related to the magnetization state of the ferromagnetic layer. The magnetization state of the ferromagnetic layer can be set to correspond to different values of a data item to be stored in the hybrid memory device. The magnetization state is non-volatile, and a write circuit can be coupled to the ferromagnetic layer to reset or change the magnetization state to a different value. The memory device can also be fabricated to include an associated transistor (or other suitable switch) that functions as an isolation element to reduce cross-talk and as a selector for the output of the device when such is used in a memory array.
    Type: Application
    Filed: May 24, 2004
    Publication date: October 28, 2004
    Inventor: Mark B. Johnson
  • Publication number: 20040213042
    Abstract: A new magnetic spin device can be used as a memory element or logic gate, such as an OR, AND, NOT, NOR and NAND gate. The state of the magnetic spin device is set inductively. A magnetic spin transistor/gate can be operated with current gain. Furthermore, inductive coupling permits the linking of multiple spin transistors and spin transistor gates to perform combinational tasks. A half adder embodiment is specifically described, and other logic gates and combinations of half adders can be constructed to perform arithmetic functions as part of a microprocessor.
    Type: Application
    Filed: May 24, 2004
    Publication date: October 28, 2004
    Inventor: Mark B. Johnson