Patents by Inventor Jijun Sun

Jijun Sun 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: 10347828
    Abstract: A magnetoresistive element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer, having a high-iron alloy interface region located along a surface of the free magnetic layer, wherein the high-iron alloy interface region has at least 50% iron by atomic composition, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. The magnetoresistive element further includes a second dielectric, having a first surface that is in contact with the surface of the free magnetic layer, and an electrode, disposed between the second dielectric and a conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion having at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Grant
    Filed: December 21, 2018
    Date of Patent: July 9, 2019
    Assignee: Everspin Technologies, Inc.
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Publication number: 20190165253
    Abstract: A magnetically free region of magnetoresistive device includes at least a first ferromagnetic region and a second ferromagnetic region separated by a non-magnetic insertion region. At least one of the first ferromagnetic region and the second ferromagnetic region may include at least a boron-rich ferromagnetic layer positioned proximate a boron-free ferromagnetic layer.
    Type: Application
    Filed: November 13, 2018
    Publication date: May 30, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Jijun SUN, Jon SLAUGHTER, Renu WHIG
  • Publication number: 20190157549
    Abstract: A method of fabricating a magnetoresistive device includes forming a magnetically fixed region on one side of an intermediate region. Forming the magnetically fixed region may include forming a first ferromagnetic region and forming an antiferromagnetic coupling region on one side of the first ferromagnetic region. The method may also include treating a surface of the coupling region by exposing the surface to a gas, and forming a second ferromagnetic region on the treated surface of the coupling region.
    Type: Application
    Filed: November 14, 2018
    Publication date: May 23, 2019
    Applicant: Everspin Technologies, Inc.
    Inventor: Jijun SUN
  • Publication number: 20190123098
    Abstract: A magnetoresistive stack/structure and method of manufacturing same comprising wherein the stack/structure includes a seed region, a fixed magnetic region disposed on and in contact with the seed region, a dielectric layer(s) disposed on the fixed magnetic region and a free magnetic region disposed on the dielectric layer(s). In one embodiment, the seed region comprises an alloy including nickel and chromium having (i) a thickness greater than or equal to 40 Angstroms (+/?10%) and less than or equal to 60 Angstroms (+/?10%), and (ii) a material composition or content of chromium within a range of 25-60 atomic percent (+/?10%) or 30-50 atomic percent (+/?10%).
    Type: Application
    Filed: November 19, 2018
    Publication date: April 25, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Jijun SUN, Sanjeev Aggarwal, Han-Jong Chia, Jon M. Slaughter, Renu Whig
  • Publication number: 20190123268
    Abstract: A magnetoresistive element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer, having a high-iron alloy interface region located along a surface of the free magnetic layer, wherein the high-iron alloy interface region has at least 50% iron by atomic composition, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. The magnetoresistive element further includes a second dielectric, having a first surface that is in contact with the surface of the free magnetic layer, and an electrode, disposed between the second dielectric and a conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion having at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Application
    Filed: December 21, 2018
    Publication date: April 25, 2019
    Applicant: EVERSPIN TECHNOLOGIES, INC.
    Inventors: Renu WHIG, Jijun SUN, Nicholas RIZZO, Jon SLAUGHTER, Dimitri HOUSSAMEDDINE, Frederick MANCOFF
  • Patent number: 10199574
    Abstract: A magnetoresistive element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer, having a high-iron alloy interface region located along a surface of the free magnetic layer, wherein the high-iron alloy interface region has at least 50% iron by atomic composition, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. The magnetoresistive element further includes a second dielectric, having a first surface that is in contact with the surface of the free magnetic layer, and an electrode, disposed between the second dielectric and a conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion having at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Grant
    Filed: March 30, 2018
    Date of Patent: February 5, 2019
    Assignee: Everspin Technologies, Inc.
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Publication number: 20180226574
    Abstract: A magnetoresistive element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer, having a high-iron alloy interface region located along a surface of the free magnetic layer, wherein the high-iron alloy interface region has at least 50% iron by atomic composition, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. The magnetoresistive element further includes a second dielectric, having a first surface that is in contact with the surface of the free magnetic layer, and an electrode, disposed between the second dielectric and a conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion having at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Application
    Filed: March 30, 2018
    Publication date: August 9, 2018
    Applicant: Everspin Technologies, Inc.
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Patent number: 9947865
    Abstract: A magnetoresistive element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer, having a high-iron alloy interface region located along a surface of the free magnetic layer, wherein the high-iron alloy interface region has at least 50% iron by atomic composition, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. The magnetoresistive element further includes a second dielectric, having a first surface that is in contact with the surface of the free magnetic layer, and an electrode, disposed between the second dielectric and a conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion having at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Grant
    Filed: January 6, 2017
    Date of Patent: April 17, 2018
    Assignee: Everspin Technologies, Inc.
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Publication number: 20170125663
    Abstract: A method of manufacturing a magnetoresistive stack/structure comprising etching through a second magnetic region to (i) provide sidewalls of the second magnetic region and (ii) expose a surface of a dielectric layer; depositing a first encapsulation layer on the sidewalls of the second magnetic region and over the dielectric layer; etching the first encapsulation layer which is disposed over the exposed surface of the dielectric layer. The method further includes (a) depositing a second encapsulation layer: (i) on the first encapsulation layer disposed on the sidewalls of the second magnetic region and (ii) over the exposed surface of the dielectric layer and (b) depositing a third encapsulation layer: (i) on the second encapsulation layer which is on the first encapsulation layer and the exposed surface of the dielectric layer. The method also includes etching the remaining layers of the stack/structure (via one or more etch processes).
    Type: Application
    Filed: October 28, 2016
    Publication date: May 4, 2017
    Inventors: Kerry Joseph Nagel, Wenchin Lin, Sarin A. Deshpande, Jijun Sun, Sanjeev Aggarwal, Chaitanya Mudivarthi
  • Publication number: 20170125670
    Abstract: A magnetoresistive element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer, having a high-iron alloy interface region located along a surface of the free magnetic layer, wherein the high-iron alloy interface region has at least 50% iron by atomic composition, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. The magnetoresistive element further includes a second dielectric, having a first surface that is in contact with the surface of the free magnetic layer, and an electrode, disposed between the second dielectric and a conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion having at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Application
    Filed: January 6, 2017
    Publication date: May 4, 2017
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Patent number: 9640753
    Abstract: A sensor and fabrication process are provided for forming reference layers with substantially orthogonal magnetization directions having zero offset with a small compensation angle. An exemplary embodiment includes a sensor layer stack of a magnetoresistive thin-film based magnetic field sensor, the sensor layer stack comprising a pinning layer; a pinned layer including a layer of amorphous material over the pinning layer, and a first layer of crystalline material over the layer of amorphous material; a nonmagnetic coupling layer over the pinned layer; a fixed layer over the nonmagnetic coupling layer; a tunnel barrier over the fixed layer; and a sense layer over the nonmagnetic intermediate layer. Another embodiment includes a sensor layer stack where a pinned layer including two crystalline layers separated by a amorphous layer.
    Type: Grant
    Filed: January 30, 2014
    Date of Patent: May 2, 2017
    Assignee: EVERSPIN TECHNOLOGIES, INC.
    Inventors: Jijun Sun, Phillip Mather, Srinivas Pietambaram, Jon Slaughter, Renu Whig, Nicholas Rizzo
  • Patent number: 9553258
    Abstract: A magnetoresistive memory element (for example, a spin-torque magnetoresistive memory element), includes first and second dielectric layers, wherein at least one of the dielectric layers is a magnetic tunnel junction. The memory element also includes a free magnetic layer having a first surface in contact with the first dielectric layer and a second surface in contact with the second dielectric layer. The free magnetic layer, which is disposed between the first and second dielectric layers, includes (i) a first high-iron interface region located along the first surface of the free magnetic layer, wherein the first high-iron interface region has at least 50% iron by atomic composition, and (ii) a first layer of ferromagnetic material adjacent to the first high-iron interface region, the first high-iron interface region between the first layer of ferromagnetic material and the first surface of the free magnetic layer.
    Type: Grant
    Filed: September 21, 2015
    Date of Patent: January 24, 2017
    Assignee: Everspin Technologies, Inc.
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Patent number: 9419208
    Abstract: A magnetoresistive memory element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer having perpendicular magnetic anisotropy, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. A first surface of the first dielectric is in contact with a first surface of the free magnetic layer. The magnetoresistive memory element further includes a second dielectric, having a first surface that is in contact with a second surface of the free magnetic layer, a conductor, including electrically conductive material, and an electrode, disposed between the second dielectric and the conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion including at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Grant
    Filed: February 18, 2016
    Date of Patent: August 16, 2016
    Assignee: Everspin Technologies, Inc.
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Publication number: 20160163964
    Abstract: A magnetoresistive memory element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer having perpendicular magnetic anisotropy, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. A first surface of the first dielectric is in contact with a first surface of the free magnetic layer. The magnetoresistive memory element further includes a second dielectric, having a first surface that is in contact with a second surface of the free magnetic layer, a conductor, including electrically conductive material, and an electrode, disposed between the second dielectric and the conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion including at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Application
    Filed: February 18, 2016
    Publication date: June 9, 2016
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Patent number: 9281168
    Abstract: The magnetic characteristics of a magnetoresistive device are improved by rendering magnetic debris non-magnetic during processing operations. Further improvement is realized by annealing the partially- or fully-formed device in the presence of a magnetic field in order to eliminate or stabilize magnetic micro-pinning sites or other magnetic abnormalities within the magnetoresistive stack for the device. Such improvement in magnetic characteristics decreases deviation in switching characteristics in arrays of such magnetoresistive devices such as those present in MRAMs.
    Type: Grant
    Filed: June 6, 2014
    Date of Patent: March 8, 2016
    Assignee: Everspin Technologies, Inc.
    Inventors: Chaitanya Mudivarthi, Jason Allen Janesky, Jijun Sun, Frederick Bennett Mancoff, Sanjeev Aggarwal
  • Publication number: 20160013401
    Abstract: A magnetoresistive memory element (for example, a spin-torque magnetoresistive memory element), includes first and second dielectric layers, wherein at least one of the dielectric layers is a magnetic tunnel junction. The memory element also includes a free magnetic layer having a first surface in contact with the first dielectric layer and a second surface in contact with the second dielectric layer. The free magnetic layer, which is disposed between the first and second dielectric layers, includes (i) a first high-iron interface region located along the first surface of the free magnetic layer, wherein the first high-iron interface region has at least 50% iron by atomic composition, and (ii) a first layer of ferromagnetic material adjacent to the first high-iron interface region, the first high-iron interface region between the first layer of ferromagnetic material and the first surface of the free magnetic layer.
    Type: Application
    Filed: September 21, 2015
    Publication date: January 14, 2016
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Publication number: 20150357560
    Abstract: The magnetic characteristics of a magnetoresistive device are improved by rendering magnetic debris non-magnetic during processing operations. Further improvement is realized by annealing the partially- or fully-formed device in the presence of a magnetic field in order to eliminate or stabilize magnetic micro-pinning sites or other magnetic abnormalities within the magnetoresistive stack for the device. Such improvement in magnetic characteristics decreases deviation in switching characteristics in arrays of such magnetoresistive devices such as those present in MRAMs.
    Type: Application
    Filed: June 6, 2014
    Publication date: December 10, 2015
    Inventors: Chaitanya Mudivarthi, Jason Allen Janesky, Jijun Sun, Frederick Bennett Mancoff, Sanjeev Aggarwal
  • Patent number: 9159906
    Abstract: A spin-torque magnetoresistive memory element has a high magnetoresistance and low current density. A free magnetic layer is positioned between first and second spin polarizers. A first tunnel barrier is positioned between the first spin polarizer and the free magnetic layer and a second tunnel barrier is positioned between the second spin polarizer and the free magnetic layer. The magnetoresistance ratio of the second tunnel barrier has a value greater than double the magnetoresistance ratio of the first tunnel barrier.
    Type: Grant
    Filed: March 19, 2014
    Date of Patent: October 13, 2015
    Assignee: Everspin Technologies, Inc.
    Inventors: Renu Whig, Jon Slaughter, Nicholas Rizzo, Jijun Sun, Frederick Mancoff, Dimitri Houssameddine
  • Publication number: 20140217528
    Abstract: A spin-torque magnetoresistive memory element has a high magnetoresistance and low current density. A free magnetic layer is positioned between first and second spin polarizers. A first tunnel barrier is positioned between the first spin polarizer and the free magnetic layer and a second tunnel barrier is positioned between the second spin polarizer and the free magnetic layer. The magnetoresistance ratio of the second tunnel barrier has a value greater than double the magnetoresistance ratio of the first tunnel barrier.
    Type: Application
    Filed: March 19, 2014
    Publication date: August 7, 2014
    Applicant: EVERSPIN TECHNOLOGIES, INC.
    Inventors: Renu Whig, Jon Slaughter, Nicholas Rizzo, Jijun Sun, Frederick Mancoff, Dimitri Houssameddine
  • Publication number: 20140159179
    Abstract: A sensor and fabrication process are provided for forming reference layers with substantially orthogonal magnetization directions having zero offset with a small compensation angle. An exemplary embodiment includes a sensor layer stack of a magnetoresistive thin-film based magnetic field sensor, the sensor layer stack comprising a pinning layer; a pinned layer including a layer of amorphous material over the pinning layer, and a first layer of crystalline material over the layer of amorphous material; a nonmagnetic coupling layer over the pinned layer; a fixed layer over the nonmagnetic coupling layer; a tunnel barrier over the fixed layer; and a sense layer over the nonmagnetic intermediate layer. Another embodiment includes a sensor layer stack where a pinned layer including two crystalline layers separated by a amorphous layer.
    Type: Application
    Filed: January 30, 2014
    Publication date: June 12, 2014
    Applicant: EVERSPIN TECHNOLOGIES, INC.
    Inventors: Jijun Sun, Phillip Mather, Srinivas Pietambaram, Jon Slaughter, Renu Whig, Nicholas Rizzo