Patents by Inventor Virat Vasav Mehta

Virat Vasav Mehta 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: 11942126
    Abstract: Provided is a magnetoresistive random-access memory (MRAM) cell. The MRAM cell comprises a top contact, a hard mask layer below the top contact, and a magnetic tunnel junction (MTJ) below the hard mask layer. The MRAM cell further comprises a diffusion barrier below the MTJ, a bottom contact below the diffusion barrier, and a magnetic liner arranged around the bottom contact.
    Type: Grant
    Filed: May 26, 2021
    Date of Patent: March 26, 2024
    Assignee: International Business Machines Corporation
    Inventors: Michael Rizzolo, Saba Zare, Virat Vasav Mehta, Eric Raymond Evarts
  • Patent number: 11793001
    Abstract: A spin-orbit torque magnetoresistive random-access memory device formed by fabricating a spin-Hall-effect (SHE) layer above and in electrical contact with a transistor, forming a spin-orbit-torque (SOT) magnetoresistive random access memory (MRAM) cell stack disposed above and in electrical contact with the SHE rail, wherein the SOT-MRAM cell stack comprises a free layer, a tunnel junction layer, a reference layer, and a diode structure, forming a write line disposed in electrical contact with the SHE rail, forming a protective dielectric layer covering a portion of the SOT-MRAM cell stack, and forming a read line disposed above and adjacent to the diode structure.
    Type: Grant
    Filed: August 13, 2021
    Date of Patent: October 17, 2023
    Assignee: International Business Machines Corporation
    Inventors: Eric Raymond Evarts, Virat Vasav Mehta, Oscar van der Straten
  • Patent number: 11665974
    Abstract: An embodiment of the invention may include a magnetic random-access memory (MRAM) structure and method of making the structure. The MRAM structure may include a magnetic tunnel junction stack. The MRAM structure may include a magnetic liner located between the magnetic tunnel junction stack and a top contact, where the magnetic liner may be a ferromagnetic material. This may enable the magnetic liner to act as an independent variable to balance many of the magnetic parameters in the MTJ film stack in order to achieve zero magnetic field at the MTJ layer.
    Type: Grant
    Filed: January 27, 2021
    Date of Patent: May 30, 2023
    Assignee: International Business Machines Corporation
    Inventors: Michael Rizzolo, Saba Zare, Virat Vasav Mehta, Eric Raymond Evarts
  • Publication number: 20230046923
    Abstract: A spin-orbit torque magnetoresistive random-access memory device formed by fabricating a spin-Hall-effect (SHE) layer above and in electrical contact with a transistor, forming a spin-orbit-torque (SOT) magnetoresistive random access memory (MRAM) cell stack disposed above and in electrical contact with the SHE rail, wherein the SOT-MRAM cell stack comprises a free layer, a tunnel junction layer, a reference layer, and a diode structure, forming a write line disposed in electrical contact with the SHE rail, forming a protective dielectric layer covering a portion of the SOT-MRAM cell stack, and forming a read line disposed above and adjacent to the diode structure.
    Type: Application
    Filed: August 13, 2021
    Publication date: February 16, 2023
    Inventors: Eric Raymond Evarts, Virat Vasav Mehta, Oscar van der Straten
  • Publication number: 20220383921
    Abstract: Provided is a magnetoresistive random-access memory (MRAM) cell. The MRAM cell comprises a top contact, a hard mask layer below the top contact, and a magnetic tunnel junction (MTJ) below the hard mask layer. The MRAM cell further comprises a diffusion barrier below the MTJ, a bottom contact below the diffusion barrier, and a magnetic liner arranged around the bottom contact.
    Type: Application
    Filed: May 26, 2021
    Publication date: December 1, 2022
    Inventors: Michael Rizzolo, Saba Zare, Virat Vasav Mehta, Eric Raymond Evarts
  • Publication number: 20220238794
    Abstract: An embodiment of the invention may include a magnetic random-access memory (MRAM) structure and method of making the structure. The MRAM structure may include a magnetic tunnel junction stack. The MRAM structure may include a magnetic liner located between the magnetic tunnel junction stack and a top contact, where the magnetic liner may be a ferromagnetic material. This may enable the magnetic liner to act as an independent variable to balance many of the magnetic parameters in the MTJ film stack in order to achieve zero magnetic field at the MTJ layer.
    Type: Application
    Filed: January 27, 2021
    Publication date: July 28, 2022
    Inventors: Michael Rizzolo, Saba Zare, Virat Vasav Mehta, Eric Raymond Evarts
  • Publication number: 20220180911
    Abstract: An apparatus comprising a magnetic tunnel junction (MTJ), a diffusion barrier, wherein the MTJ is located on the diffusion barrier and a bottom contact that includes a magnetic field generating component, wherein the diffusion barrier is located on top of the bottom contact, wherein the magnetic field generated by the magnetic field generating component affects the stability of the MTJ.
    Type: Application
    Filed: December 7, 2020
    Publication date: June 9, 2022
    Inventors: Saba Zare, Michael Rizzolo, Virat Vasav Mehta, Eric Raymond Evarts, Theodorus E. Standaert
  • Patent number: 11226252
    Abstract: A sub-micrometer pressure sensor is provided that includes a multilayered magnetic tunnel junction (MTJ) pillar that contains a non-magnetic metallic spacer separating a first magnetic free layer from a second magnetic free layer. The presence of the non-magnetic metallic spacer in the multilayered MTJ pillar improves the sensitivity without compromising area, and makes the pressure sensor binary (either “on” or “off”) with little or no drift, and sensitivity change over time. Moreover, the resistivity switch in such a pressure sensor is instantly and a low error rate is observed.
    Type: Grant
    Filed: January 7, 2019
    Date of Patent: January 18, 2022
    Assignee: International Business Machines Corporation
    Inventors: Virat Vasav Mehta, Alexander Reznicek, Chandrasekharan Kothandaraman, Eric Raymond Evarts, Pouya Hashemi
  • Patent number: 11114607
    Abstract: A method of manufacturing a double magnetic tunnel junction device is provided. The method includes forming a first magnetic tunnel junction stack. The first magnetic tunnel junction stack includes a first reference layer. The method also includes forming a second magnetic tunnel junction stack, where the second magnetic tunnel junction stack includes a second reference layer. The method also includes bonding the first magnetic tunnel junction stack to the second magnetic tunnel junction stack with ultra-high vacuum bonding to form the double magnetic tunnel junction device.
    Type: Grant
    Filed: November 22, 2019
    Date of Patent: September 7, 2021
    Assignee: International Business Machines Corporation
    Inventors: Alexander Reznicek, Virat Vasav Mehta
  • Patent number: 11114146
    Abstract: An erasable magnetoresistive random-access memory (MRAM) structure and a method of making the same includes an MRAM cell disposed between bit line and word line circuit elements, and a vertical-cavity surface-emitting laser (VCSEL) element disposed above the MRAM cell. A laser output of the VCSEL is directed toward the MRAM cell.
    Type: Grant
    Filed: November 25, 2019
    Date of Patent: September 7, 2021
    Assignee: International Business Machines Corporation
    Inventors: Alexander Reznicek, Eric Raymond Evarts, Virat Vasav Mehta, Bahman Hekmatshoartabari
  • Publication number: 20210159389
    Abstract: A method of manufacturing a double magnetic tunnel junction device is provided. The method includes forming a first magnetic tunnel junction stack. The first magnetic tunnel junction stack includes a first reference layer. The method also includes forming a second magnetic tunnel junction stack, where the second magnetic tunnel junction stack includes a second reference layer. The method also includes bonding the first magnetic tunnel junction stack to the second magnetic tunnel junction stack with ultra-high vacuum bonding to form the double magnetic tunnel junction device.
    Type: Application
    Filed: November 22, 2019
    Publication date: May 27, 2021
    Inventors: Alexander Reznicek, Virat Vasav Mehta
  • Publication number: 20210158850
    Abstract: An erasable magnetoresistive random-access memory (MRAM) structure and a method of making the same includes an MRAM cell disposed between bit line and word line circuit elements, and a vertical-cavity surface-emitting laser (VCSEL) element disposed above the MRAM cell. A laser output of the VCSEL is directed toward the MRAM cell.
    Type: Application
    Filed: November 25, 2019
    Publication date: May 27, 2021
    Inventors: Alexander Reznicek, Eric Raymond Evarts, Virat Vasav Mehta, Bahman Hekmatshoartabari
  • Patent number: 10942072
    Abstract: A sub-micrometer pressure sensor including a multilayered magnetic tunnel junction (MTJ) pillar containing a magnetostrictive material layer above or below a magnetic free layer of the multilayered MTJ pillar is provided. Advanced patterning allows for scaling of the multilayered MTJ pillar down to 25 nm or below which enables the formation of a large array of extremely high resolution pressure sensors. By varying the thickness of the magnetostrictive material layer, the sensitivity of the pressure sensor can be fine tuned. Unique magnetostrictive materials in the multilayered MTJ pillar will alter the device current with the input of external pressure. Furthermore, unique arrays with much smaller critical elements can be organized in differential sensing arrangements of the multilayered MTJ pillar with pressure sensing capability that can outperform current piezoelectric based pressure sensing arrays.
    Type: Grant
    Filed: November 20, 2018
    Date of Patent: March 9, 2021
    Assignee: International Business Machines Corporation
    Inventors: Chandrasekharan Kothandaraman, Eric Raymond Evarts, Virat Vasav Mehta, Pouya Hashemi, Alexander Reznicek
  • Publication number: 20200217735
    Abstract: A sub-micrometer pressure sensor is provided that includes a multilayered magnetic tunnel junction (MTJ) pillar that contains a non-magnetic metallic spacer separating a first magnetic free layer from a second magnetic free layer. The presence of the non-magnetic metallic spacer in the multilayered MTJ pillar improves the sensitivity without compromising area, and makes the pressure sensor binary (either “on” or “off”) with little or no drift, and sensitivity change over time. Moreover, the resistivity switch in such a pressure sensor is instantly and a low error rate is observed.
    Type: Application
    Filed: January 7, 2019
    Publication date: July 9, 2020
    Inventors: Virat Vasav Mehta, Alexander Reznicek, Chandrasekharan Kothandaraman, Eric Raymond Evarts, Pouya Hashemi
  • Publication number: 20200158582
    Abstract: A sub-micrometer pressure sensor including a multilayered magnetic tunnel junction (MTJ) pillar containing a magnetostrictive material layer above or below a magnetic free layer of the multilayered MTJ pillar is provided. Advanced patterning allows for scaling of the multilayered MTJ pillar down to 25 nm or below which enables the formation of a large array of extremely high resolution pressure sensors. By varying the thickness of the magnetostrictive material layer, the sensitivity of the pressure sensor can be fine tuned. Unique magnetostrictive materials in the multilayered MTJ pillar will alter the device current with the input of external pressure. Furthermore, unique arrays with much smaller critical elements can be organized in differential sensing arrangements of the multilayered MTJ pillar with pressure sensing capability that can outperform current piezoelectric based pressure sensing arrays.
    Type: Application
    Filed: November 20, 2018
    Publication date: May 21, 2020
    Inventors: Chandrasekharan Kothandaraman, Eric Raymond Evarts, Virat Vasav Mehta, Pouya Hashemi, Alexander Reznicek
  • Patent number: 9601144
    Abstract: A heat-assisted magnetic recording (HAMR) disk drive has a disk with at least two independent data layers (RL1 and RL2), each data layer storing an independent data stream. At a high laser power both RL1 and RL2 are heated to above their respective Curie temperatures and a first data stream is recorded in both RL1 and RL2. At a lower laser power only upper RL2 is heated to above its Curie temperature and a second data stream is recorded only in RL2. The data layers are separated by a nonmagnetic spacer layer (SL) that prevents lower RL1 from being heated to above its Curie temperature at low laser power. The first and second data streams are typically asynchronous. Recorded data is read back from both data streams simultaneously as a composite readback signal. A joint Viterbi detector detects the asynchronous data streams simultaneously from the composite readback signal.
    Type: Grant
    Filed: May 25, 2016
    Date of Patent: March 21, 2017
    Assignee: HGST Netherlands B.V.
    Inventors: Virat Vasav Mehta, James William Reiner, Michael Paul Salo, Roger William Wood
  • Patent number: 9601145
    Abstract: A heat-assisted magnetic recording (HAMR) disk has multiple independent data layers, each data layer being a continuous non-patterned layer of magnetizable material. Each data layer can store data independent and not related to the data stored in the other data layers. The data layers are separated by a nonmagnetic spacer layer (SL) and each data layer is formed of high-anisotropy (Ku) material so that the coercivities of lower and upper data layers (RL1 and RL2) are greater than the magnetic write field. At a high laser power both RL1 and RL2 are heated to above their respective Curie temperatures and data is recorded in both RL1 and RL2. At low laser power only upper RL2 is heated to above its Curie temperature and data is recorded only in RL2. The SL prevents lower RL1 from being heated to above its Curie temperature at low laser power.
    Type: Grant
    Filed: May 25, 2016
    Date of Patent: March 21, 2017
    Assignee: HGST Netherlands B.V.
    Inventors: Michael Konrad Grobis, Virat Vasav Mehta, Gregory John Parker, Hal Jervis Rosen, Bruce David Terris