Patents by Inventor Tiffany Santos

Tiffany Santos 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).

  • Publication number: 20240064992
    Abstract: A semiconductor memory device includes an alternating stack of insulating layers and electrically conductive layers, a memory opening vertically extending through the alternating stack, and a memory opening fill structure located in the memory opening and including a vertical stack of discrete ferroelectric material portions and a vertical semiconductor channel. In one embodiment, the discrete ferroelectric material portions include a ferroelectric alloy material of a first dielectric metal oxide material and a second dielectric metal oxide material. In another embodiment, each of the discrete ferroelectric material portions is oxygen-deficient.
    Type: Application
    Filed: August 19, 2022
    Publication date: February 22, 2024
    Inventors: Rahul SHARANGPANI, Kartik SONDHI, Raghuveer S. MAKALA, Tiffany SANTOS, Fei ZHOU, Joyeeta NAG, Bhagwati PRASAD
  • Publication number: 20240064991
    Abstract: A semiconductor memory device includes an alternating stack of insulating layers and electrically conductive layers, a memory opening vertically extending through the alternating stack, and a memory opening fill structure located in the memory opening and including a vertical stack of discrete ferroelectric material portions and a vertical semiconductor channel. In one embodiment, the discrete ferroelectric material portions include a ferroelectric alloy material of a first dielectric metal oxide material and a second dielectric metal oxide material. In another embodiment, each of the discrete ferroelectric material portions is oxygen-deficient.
    Type: Application
    Filed: August 19, 2022
    Publication date: February 22, 2024
    Inventors: Kartik SONDHI, Rahul SHARANGPANI, Raghuveer S. MAKALA, Tiffany SANTOS, Fei ZHOU, Joyeeta NAG, Bhagwati PRASAD, Adarsh RAJASHEKHAR
  • Publication number: 20230107190
    Abstract: A magnetic tunnel junction may include a platinum-containing layer including at least one of Ir, Hf or Ru in contact with a free layer, or a combination of a platinum layer and a Hf or Ir layer formed on opposite sides of a free layer.
    Type: Application
    Filed: December 13, 2022
    Publication date: April 6, 2023
    Inventors: Alan KALITSOV, Bhagwati PRASAD, Rajesh CHOPDEKAR, Lei WAN, Tiffany SANTOS
  • Patent number: 11443790
    Abstract: A magnetoresistive memory device includes a first electrode, a second electrode that is spaced from the first electrode, and a perpendicular magnetic tunnel junction layer stack located between the first electrode and the second electrode. The perpendicular magnetic tunnel junction layer stack includes, from one side to another: a reference layer having a fixed reference magnetization direction, a first spinel layer located including a first polycrystalline spinel material having (001) texture along an axial direction that is perpendicular to an interface with the reference layer, a magnesium oxide layer including a polycrystalline magnesium oxide material having (001) texture along the axial direction, a second spinel layer including a second polycrystalline spinel material having (001) texture along the axial direction, and a ferromagnetic free layer.
    Type: Grant
    Filed: March 4, 2021
    Date of Patent: September 13, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Derek Stewart, Matthew Carey, Tiffany Santos
  • Publication number: 20220139435
    Abstract: A spin-transfer torque (STT) magnetoresistive memory device includes a first electrode, a second electrode, and a magnetic tunnel junction located between the first electrode and the second electrode. The magnetic tunnel junction includes a reference layer having a fixed magnetization direction, a free layer stack, and a nonmagnetic tunnel barrier layer located between the reference layer and the free layer stack. The free layer stack has a total thickness of less than 2 nm, and contains in order, a proximal ferromagnetic layer located proximal to the nonmagnetic tunnel barrier layer, a first non-magnetic metal sub-monolayer, an intermediate ferromagnetic layer, a second non-magnetic metal sub-monolayer, and a distal ferromagnetic layer.
    Type: Application
    Filed: January 14, 2022
    Publication date: May 5, 2022
    Inventors: Tiffany SANTOS, Neil SMITH
  • Publication number: 20220036934
    Abstract: A magnetoresistive memory device includes a first electrode, a second electrode that is spaced from the first electrode, and a perpendicular magnetic tunnel junction layer stack located between the first electrode and the second electrode. The perpendicular magnetic tunnel junction layer stack includes, from one side to another: a reference layer having a fixed reference magnetization direction, a first spinel layer located including a first polycrystalline spinel material having (001) texture along an axial direction that is perpendicular to an interface with the reference layer, a magnesium oxide layer including a polycrystalline magnesium oxide material having (001) texture along the axial direction, a second spinel layer including a second polycrystalline spinel material having (001) texture along the axial direction, and a ferromagnetic free layer.
    Type: Application
    Filed: March 4, 2021
    Publication date: February 3, 2022
    Inventors: Bhagwati PRASAD, Derek STEWART, Matthew CAREY, Tiffany SANTOS
  • Patent number: 11031058
    Abstract: A spin-transfer torque (STT) magnetoresistive memory device includes a first electrode, a second electrode, and a magnetic tunnel junction located between the first electrode and the second electrode. The magnetic tunnel junpction includes a reference layer having a fixed magnetization direction, a free layer stack, and a nonmagnetic tunnel barrier layer located between the reference layer and the free layer stack. The free layer stack has a total thickness of less than 2 nm, and contains in order, a proximal ferromagnetic layer located proximal to the nonmagnetic tunnel barrier layer, a first non-magnetic metal sub-monolayer, an intermediate ferromagnetic layer, a second non-magnetic metal sub-monolayer, and a distal ferromagnetic layer.
    Type: Grant
    Filed: September 3, 2019
    Date of Patent: June 8, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Tiffany Santos, Neil Smith
  • Patent number: 11004489
    Abstract: A perpendicular spin transfer torque MRAM memory cell includes a magnetic tunnel junction stack comprising a pinned layer having a fixed direction of magnetization, a free layer having a direction of magnetization that can be switched, a tunnel barrier between the pinned layer and the free layer, a cap layer above the free layer and one or more in-stack multi-layer thermal barrier layers having multiple internal interfaces between materials. The thermal barrier layers have high enough thermal resistivity to maintain the heat generated in the memory cell and low enough electrical resistivity to not materially change the electrical resistance of the memory cell. One embodiment further includes a thermal barrier liner surrounding the free layer, pinned layer, tunnel barrier and cap layer.
    Type: Grant
    Filed: July 1, 2019
    Date of Patent: May 11, 2021
    Assignee: Western Digital Technologies, Inc.
    Inventors: Goran Mihajlovic, Tiffany Santos, Michael Grobis
  • Publication number: 20210065761
    Abstract: A spin-transfer torque (STT) magnetoresistive memory device includes a first electrode, a second electrode, and a magnetic tunnel junction located between the first electrode and the second electrode. The magnetic tunnel junpction includes a reference layer having a fixed magnetization direction, a free layer stack, and a nonmagnetic tunnel barrier layer located between the reference layer and the free layer stack. The free layer stack has a total thickness of less than 2 nm, and contains in order, a proximal ferromagnetic layer located proximal to the nonmagnetic tunnel barrier layer, a first non-magnetic metal sub-monolayer, an intermediate ferromagnetic layer, a second non-magnetic metal sub-monolayer, and a distal ferromagnetic layer.
    Type: Application
    Filed: September 3, 2019
    Publication date: March 4, 2021
    Inventors: Tiffany SANTOS, Neil SMITH
  • Publication number: 20200402559
    Abstract: A perpendicular spin transfer torque MRAM memory cell includes a magnetic tunnel junction stack comprising a pinned layer having a fixed direction of magnetization, a free layer having a direction of magnetization that can be switched, a tunnel barrier between the pinned layer and the free layer, a cap layer above the free layer and one or more in-stack multi-layer thermal barrier layers having multiple internal interfaces between materials. The thermal barrier layers have high enough thermal resistivity to maintain the heat generated in the memory cell and low enough electrical resistivity to not materially change the electrical resistance of the memory cell. One embodiment further includes a thermal barrier liner surrounding the free layer, pinned layer, tunnel barrier and cap layer.
    Type: Application
    Filed: July 1, 2019
    Publication date: December 24, 2020
    Applicant: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Goran Mihajlovic, Tiffany Santos, Michael Grobis
  • Patent number: 10832750
    Abstract: A perpendicular spin transfer torque MRAM memory cell includes a magnetic tunnel junction that has a free layer, a pinned layer and a tunnel barrier between the free layer and the pinned layer. The free layer has a switchable direction of magnetization perpendicular to the plane of the free layer. A cap layer is provided adjacent to the magnetic tunnel junction. The thickness of the cap layer is increased so that the cap layer acts as a heating layer, which results in a reduction of the current density during writing and increases the write margin. In some embodiments, a resistive heating layer is added to the memory cell, adjacent to the cap layer, in order to achieve the lower current density and increased write margin while also improving signal to noise ration during reading by eliminating shot noise.
    Type: Grant
    Filed: February 22, 2019
    Date of Patent: November 10, 2020
    Assignee: SanDisk Technologies LLC
    Inventors: Goran Mihajlovic, Tiffany Santos, Jui-Lung Li
  • Publication number: 20200273510
    Abstract: A perpendicular spin transfer torque MRAM memory cell includes a magnetic tunnel junction that has a free layer, a pinned layer and a tunnel barrier between the free layer and the pinned layer. The free layer has a switchable direction of magnetization perpendicular to the plane of the free layer. A cap layer is provided adjacent to the magnetic tunnel junction. The thickness of the cap layer is increased so that the cap layer acts as a heating layer, which results in a reduction of the current density during writing and increases the write margin. In some embodiments, a resistive heating layer is added to the memory cell, adjacent to the cap layer, in order to achieve the lower current density and increased write margin while also improving signal to noise ration during reading by eliminating shot noise.
    Type: Application
    Filed: February 22, 2019
    Publication date: August 27, 2020
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Goran Mihajlovic, Tiffany Santos, Jui-Lung Li