Patents Assigned to EverSpin Technologies, Inc.
  • 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: 20190157550
    Abstract: A magnetoresistive structure having two dielectric layers, and method of manufacturing same, includes a free magnetic layer positioned between the two dielectric layers. The method of manufacture comprises at least two etch processes and at least one encapsulation process interposed therebetween wherein the encapsulation is formed on sidewalls of the partially formed magnetoresistive stack between etch processes. For example, an exemplary method of manufacturing a magnetoresistive device includes etching through a second electrode, second dielectric layer and free magnetic layer to provide a sidewall of (i) an unpinned synthetic antiferromagnetic structure, (ii) a second dielectric layer and (iii) a free magnetic layer; thereafter, forming an encapsulation material on the sidewall of the unpinned synthetic antiferromagnetic structure, second dielectric layer and free magnetic layer, and after forming the encapsulation material, etching through a first dielectric layer.
    Type: Application
    Filed: January 24, 2019
    Publication date: May 23, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Sanjeev AGGARWAL, Kerry NAGEL, Jason Janesky
  • Publication number: 20190147971
    Abstract: In some examples, a memory device may be configured to store data in either an original or an inverted state based at least in part on a state associated with one or more shorted bit cells. For instance, the memory device may be configured to identify a shorted bit cell within a memory array and to store the data in the memory array, such that a state of the data bit stored in the shorted bit cell matches the state associated with the shorted bit cell.
    Type: Application
    Filed: January 8, 2019
    Publication date: May 16, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Thomas Andre, Jon Slaughter, Dimitri Houssameddine, Syed M. Alam
  • Publication number: 20190140167
    Abstract: A method of fabricating an integrated circuit device includes forming a trench in a dielectric material and forming a ferromagnetic circuit element having an angled surface on the trench. The angled surface of the circuit element is removed using a chemical mechanical polishing (CMP) process and the trench is filled with an electrically conductive material.
    Type: Application
    Filed: October 30, 2018
    Publication date: May 9, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Sanjeev AGGARWAL, Kerry Joseph Nagel
  • Publication number: 20190140019
    Abstract: An integrated circuit device includes a memory portion and a logic portion. The memory portion may include a plurality of magnetoresistive devices and the logic portion may include logic circuits. The memory portion may include a plurality of metal conductors separated by a first interlayer dielectric material (ILD), wherein the first ILD is a low-k ILD or an ultra low-k ILD. And, the logic portion may include a plurality of metal conductors separated by a second interlayer dielectric material (ILD).
    Type: Application
    Filed: November 8, 2018
    Publication date: May 9, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Kerry Joseph NAGEL, Sanjeev AGGARWAL, Sarin A. DESHPANDE
  • Patent number: 10281531
    Abstract: A chopping technique, and associated structure, is implemented to cancel the magnetic 1/f noise contribution in a Tunneling Magnetoresistance (TMR) field sensor. The TMR field sensor includes a first bridge circuit including multiple TMR elements to sense a magnetic field and a second circuit to apply a bipolar current pulse adjacent to each TMR element. The current lines are serially or sequentially connected to a current source to receive the bipolar current pulse. The field sensor has an output comprising a high output and a low output in response to the bipolar pulse. This asymmetric response allows a chopping technique for 1/f noise reduction in the field sensor.
    Type: Grant
    Filed: November 4, 2016
    Date of Patent: May 7, 2019
    Assignee: EVERSPIN TECHNOLOGIES, INC.
    Inventors: Bradley Neal Engel, Phillip G. Mather
  • Publication number: 20190131519
    Abstract: A magnetoresistive stack includes a seed region formed above a base region, a fixed magnetic region formed above the seed region and an intermediate region positioned between the fixed magnetic region and a free magnetic region. The base region may be formed of a material having a lower standard free energy of oxidation than iron.
    Type: Application
    Filed: November 2, 2018
    Publication date: May 2, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Sumio Ikegawa, Jon Slaughter, Renu Whig
  • Patent number: 10276789
    Abstract: A semiconductor process integrates three bridge circuits, each include magnetoresistive sensors coupled as a Wheatstone bridge on a single chip to sense a magnetic field in three orthogonal directions. The process includes various deposition and etch steps forming the magnetoresistive sensors and a plurality of flux guides on one of the three bridge circuits for transferring a ā€œZā€ axis magnetic field onto sensors orientated in the XY plane.
    Type: Grant
    Filed: January 3, 2018
    Date of Patent: April 30, 2019
    Assignee: Everspin Technologies, Inc.
    Inventors: Renu Whig, Phillip Mather, Kenneth Smith, Sanjeev Aggarwal, Jon Slaughter, Nicholas Rizzo
  • Publication number: 20190123266
    Abstract: A magnetoresistive magnetic tunnel junction (MTJ) stack includes a free magnetic region, a fixed magnetic region, and a dielectric layer positioned between the free magnetic region and the fixed magnetic region. In one aspect, the fixed magnetic region consists essentially of an unpinned, fixed synthetic anti-ferromagnetic (SAF) structure which comprises (i) a first layer of one or more ferromagnetic materials, including cobalt, (ii) a multi-layer region including a plurality of layers of ferromagnetic materials, wherein the plurality of layers of ferromagnetic materials include a layer of one or more ferromagnetic materials including cobalt, and (iii) an anti-ferromagnetic coupling layer disposed between the first layer and the multi-layer region. The free magnetic region may include a circular shape, the one or more ferromagnetic materials of the first layer may include cobalt, iron and boron, and the dielectric layer may be disposed on the first layer.
    Type: Application
    Filed: December 19, 2018
    Publication date: April 25, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Srinivas V. PIETAMBARAM, Bengt J. AKERMAN, Renu WHIG, Jason A. JANESKY, Nicholas D. RIZZO, Jon M. SLAUGHTER
  • 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
  • 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
  • Patent number: 10268591
    Abstract: A memory having a delayed write-back to the array of data corresponding to a previously opened page allows delays associated with write-back operations to be avoided. After an initial activation opens a first page and the read/write operations for that page are complete, write-back of the open page to the array of memory cells is delayed until after completion of a subsequent activate operation that opens a new page. Techniques to force a write-back in the absence of another activate operation are also disclosed.
    Type: Grant
    Filed: May 22, 2018
    Date of Patent: April 23, 2019
    Assignee: Everspin Technologies Inc.
    Inventors: Thomas Andre, Syed M. Alam, Chitra Subramanian, Javed S. Barkatullah
  • Patent number: 10269405
    Abstract: A memory device is configured to identify a set of bit cells to be changed from a first state to a second state. In some examples, the memory device may apply a first voltage to the set of bit cells to change a least a first portion of the set of bit cells to the second state. In some cases, the memory device may also identify a second portion of the bit cells that remained in the first state following the application of the first voltage. In these cases, the memory device may apply a second voltage having a greater magnitude, duration, or both to the second portion of the set of bit cells in order to set the second portion of bit cells to the second state.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: April 23, 2019
    Assignee: Everspin Technologies, Inc.
    Inventors: Thomas Andre, Dimitri Houssameddine, Syed M. Alam, Jon Slaughter, Chitra Subramanian
  • Publication number: 20190115060
    Abstract: Spin-orbit-torque (SOT) control strip lines are provided along the sides of free layers in perpendicular magnetic tunnel junction devices. Current flowing through such SOT control strip lines injects spin current into the free layers such that spin torque is applied to the free layers. The spin torque can be used to force the magnetic state of the free layer to a particular state based on the direction of the current through the SOT control strip line. In other embodiments, the SOT provides an assist to spin-transfer torque generated by current flowing vertically through the magnetic tunnel junction. Some embodiments have dedicated strip lines for a single magnetic tunnel junction such that a three-terminal device results.
    Type: Application
    Filed: October 11, 2018
    Publication date: April 18, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Sarin DESHPANDE, Sanjeev AGGARWAL, Jason JANESKY, Jon SLAUGHTER, Phillip LOPRESTI
  • Patent number: 10262713
    Abstract: Techniques and circuits for testing and configuring bias voltage or bias current for write operations in memory devices are presented. Registers and nonvolatile storage is included on the memory devices for storing values used to control testing of the memory devices as well as for configuring parameters related to both testing and normal operation.
    Type: Grant
    Filed: January 9, 2017
    Date of Patent: April 16, 2019
    Assignee: Everspin Technologies, Inc.
    Inventors: Jason Janesky, Syed M. Alam, Dimitri Houssameddine, Mark Deherrera
  • Patent number: 10255961
    Abstract: A magnetoresistive memory device that stores data in the synthetic antiferromagnet (SAF) included in each spin-torque memory cell provides for more robust data storage. In normal operation, the memory cells use the free portion of the memory cell for data storage. Techniques for storing data in the reference portions of memory cells are presented, where an unbalanced SAF that includes ferromagnetic layers having different magnetic moments is used to lower the switching barrier for the SAF and allow for writing data values to the SAF using lower currents and magnetic fields than would be required for a balanced SAF.
    Type: Grant
    Filed: December 22, 2017
    Date of Patent: April 9, 2019
    Assignee: Everspin Technologies, Inc.
    Inventors: Han-Jong Chia, Sumio Ikegawa, Michael Tran, Jon Slaughter
  • Patent number: 10255216
    Abstract: In some examples, a communications device includes a magnetic memory accessible by both a central processing unit and a digital signal processor to enable the central processing unit to assist the digital signal processor in establishing and maintaining a communication channel. The communication device is configured to re-establish communications in the event of an interruption in the communication channel or if the communication device experiences a power loss event.
    Type: Grant
    Filed: November 14, 2014
    Date of Patent: April 9, 2019
    Assignee: Everspin Technologies, Inc.
    Inventor: Sadfar Asghar
  • Patent number: 10256840
    Abstract: A memory device includes memory arrays configured to store pages of data organized into multiple ECC words. The memory device also includes at least one input/output pad for each ECC word associated with a page. The memory device is configurable to perform a first level of error correction on each of the ECC words associated with the page. A system-level error correction circuit is configurable to perform a second level of error correction on the data output by each of the input/output pads during a particular period of time. Each of the one or more input/output pads of the memory device is configurable to provide only one bit of data per ECC word to an external source during an access from an external source.
    Type: Grant
    Filed: December 20, 2016
    Date of Patent: April 9, 2019
    Assignee: Everspin Technologies, Inc.
    Inventors: Syed M. Alam, Thomas Andre
  • Publication number: 20190103555
    Abstract: A method of manufacturing one or more interconnects to magnetoresistive structure comprising (i) depositing a first conductive material in a via; (2) etching the first conductive material wherein, after etching the first conductive material a portion of the first conductive material remains in the via, (3) partially filling the via by depositing a second conductive material in the via and directly on the first conductive material in the via; (4) depositing a first electrode material in the via and directly on the second conductive material in the via; (5) polishing a first surface of the first electrode material wherein, after polishing, the first electrode material is (i) on the second conductive material in the via and (ii) over the portion of the first conductive material remaining in the via; and (6) forming a magnetoresistive structure over the first electrode material.
    Type: Application
    Filed: November 19, 2018
    Publication date: April 4, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Kerry Joseph NAGEL, Kenneth H. SMITH, Moazzem HOSSAIN, Sanjeev AGGARWAL
  • Publication number: 20190103554
    Abstract: A method of fabricating a magnetoresistive bit from a magnetoresistive stack includes etching through a first portion of the magnetoresistive stack using a first etch process to form one or more sidewalls. At least a portion of the sidewalls includes redeposited material after the etching. The method also includes modifying at least a portion of the redeposited material on the sidewalls, and etching through a second portion of the magnetoresistive stack after the modifying step. The magnetoresistive stack may include a first magnetic region, an intermediate region disposed over the first magnetic region, and a second magnetic region disposed over the intermediate region.
    Type: Application
    Filed: August 21, 2018
    Publication date: April 4, 2019
    Applicant: Everspin Technologies, Inc.
    Inventors: Sanjeev AGGARWAL, Sarin A. Deshpande, Kerry Joseph Nagel