Patents by Inventor Michael K. Grobis

Michael K. Grobis 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: 11972787
    Abstract: Technology is disclosed herein for refreshing threshold switching selectors in programmable resistance memory cells in cross-point memory arrays. The Vt of the threshold switching selector may drift over time. The memory system resets the Vt of the threshold switching selectors with a selector refresh operation and uses a separate data refresh operation to refresh data in programmable resistance memory elements. The data refresh operation itself may also refresh the selector. However, the threshold switching selector refresh operation is faster than the data refresh operation. Moreover, the selector refresh operation consumes much less power and/or current then the data refresh operation. The selector refresh operation may thus be performed at a higher rate than the data refresh operation.
    Type: Grant
    Filed: May 25, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Michael Nicolas Albert Tran, Michael K. Grobis, Ward Parkinson, Nathan Franklin
  • Publication number: 20230386543
    Abstract: Technology is disclosed herein for refreshing threshold switching selectors in programmable resistance memory cells in cross-point memory arrays. The Vt of the threshold switching selector may drift over time. The memory system resets the Vt of the threshold switching selectors with a selector refresh operation and uses a separate data refresh operation to refresh data in programmable resistance memory elements. The data refresh operation itself may also refresh the selector. However, the threshold switching selector refresh operation is faster than the data refresh operation. Moreover, the selector refresh operation consumes much less power and/or current then the data refresh operation. The selector refresh operation may thus be performed at a higher rate than the data refresh operation.
    Type: Application
    Filed: May 25, 2022
    Publication date: November 30, 2023
    Applicant: SanDisk Technologies LLC
    Inventors: Michael Nicolas Albert Tran, Michael K. Grobis, Ward Parkinson, Nathan Franklin
  • Publication number: 20230360700
    Abstract: Technology is disclosed for a memory system having a cross-point array with threshold switching selector memory cells. Each memory cell has a two-terminal threshold switching selector memory element that may be programmed to two different on-state conductances in order to store information. One bit value may be represented by a high-resistance state (HRS) when in the on-state and another bit value may be represented by a low-resistance state (LRS) when in the on-state. In one aspect, a conditioning signal is applied to the memory cell prior to programming. Applying a program signal with the opposite polarity as the conditioning signal may result in a higher conductance in the on-state than applying a program signal with the same polarity as the conditioning signal. The memory element may also serve as a selector for the memory cell. The memory element may include an Ovonic Threshold Switch (OTS).
    Type: Application
    Filed: May 3, 2022
    Publication date: November 9, 2023
    Applicant: Western Digital Technologies, Inc.
    Inventors: Hans Jurgen Richter, Michael K. Grobis
  • Patent number: 11355188
    Abstract: An apparatus is provided that includes a plurality of data arrays each comprising first memory cells, a plurality of read reference arrays each comprising second memory cells, a plurality of write reference arrays each comprising third memory cells, an access block comprising a memory cell from each of the plurality of data arrays, each of the plurality of read reference arrays, and each of the plurality of write reference arrays, and a memory controller. The memory controller is configured to determine a read threshold voltage to compensate a drift of a threshold voltage of the first memory cells, wherein the read threshold voltage is determined based on threshold voltages of a plurality of second memory cells, and a read offset voltage to compensate an offset voltage of the first memory cells, wherein the read offset voltage is determined based on offset voltages of a plurality of second memory cells.
    Type: Grant
    Filed: April 30, 2021
    Date of Patent: June 7, 2022
    Assignee: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Daniel Bedau
  • Publication number: 20210343338
    Abstract: A method is provided that includes reading a plurality of resistance-switching memory cells comprising a block of data, decoding the block of data using an error correction code decoder, and based on results of the decoding, selectively performing an overwrite-read process to read the block of data. The overwrite read process determines a change in resistance of the resistance-switching memory cells in response to a write pulse.
    Type: Application
    Filed: July 14, 2021
    Publication date: November 4, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Daniel Bedau, Christopher J. Petti
  • Publication number: 20210249073
    Abstract: An apparatus is provided that includes a plurality of data arrays each comprising first memory cells, a plurality of read reference arrays each comprising second memory cells, a plurality of write reference arrays each comprising third memory cells, an access block comprising a memory cell from each of the plurality of data arrays, each of the plurality of read reference arrays, and each of the plurality of write reference arrays, and a memory controller. The memory controller is configured to determine a read threshold voltage to compensate a drift of a threshold voltage of the first memory cells, wherein the read threshold voltage is determined based on threshold voltages of a plurality of second memory cells, and a read offset voltage to compensate an offset voltage of the first memory cells, wherein the read offset voltage is determined based on offset voltages of a plurality of second memory cells.
    Type: Application
    Filed: April 30, 2021
    Publication date: August 12, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Daniel Bedau
  • Patent number: 11081174
    Abstract: A two-step SET pulse may be applied to a phase change material of a phase change memory cell in which a first lower SET pulse is applied to make the phase change material dwell at 600K to incubate nuclei near the maximum nucleation rate and then a second higher SET pulse is immediately applied to make the phase change material dwell at 720K to maximize crystal growth. Moreover, the slope of the falling edge of a RESET pulse applied prior to the two-step SET pulse may be adjusted to increase the number of nuclei (e.g., formed with a steeper falling edge) to increase SET efficiency at the expense of a more stable amorphous phase (e.g., formed with a less steep falling edge) that improves data retention.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: August 3, 2021
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Zhaoqiang Bai, Mac D. Apodaca, Michael K. Grobis, Michael Nicolas Albert Tran, Neil Leslie Robertson, Gerardo A. Bertero
  • Patent number: 11004508
    Abstract: A memory system is provided that includes a first memory array including a first memory cell, a second memory array including a second memory cell, and a memory controller configured to determine a threshold voltage of the second memory cell to compensate a drift of a threshold voltage of the first memory cell and/or determine an offset voltage of the second memory cell to compensate an offset voltage of the first memory cell.
    Type: Grant
    Filed: August 30, 2019
    Date of Patent: May 11, 2021
    Assignee: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Daniel Bedau
  • Publication number: 20210065791
    Abstract: A memory system is provided that includes a first memory array including a first memory cell, a second memory array including a second memory cell, and a memory controller configured to determine a threshold voltage of the second memory cell to compensate a drift of a threshold voltage of the first memory cell and/or determine an offset voltage of the second memory cell to compensate an offset voltage of the first memory cell.
    Type: Application
    Filed: August 30, 2019
    Publication date: March 4, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Daniel Bedau
  • Publication number: 20200388332
    Abstract: A method is provided that includes applying a read voltage to a resistance-switching memory cell to determine a first memory cell resistance, applying a first write voltage to the resistance-switching memory cell, applying the read voltage to the resistance-switching memory cell to determine a second memory cell resistance, and comparing the first memory cell resistance to the second memory cell resistance to determine that the resistance-switching memory cell is in a first memory state or a second memory state.
    Type: Application
    Filed: July 3, 2019
    Publication date: December 10, 2020
    Applicant: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Daniel Bedau, Christopher J. Petti
  • Publication number: 20200365203
    Abstract: Systems and methods for improving the crystallization of a phase change material of a phase change memory cell are described. A two-step SET pulse may be applied to the phase change material in which a first lower SET pulse is applied to make the phase change material dwell at 600K to incubate nuclei near the maximum nucleation rate and then a second higher SET pulse is immediately applied to make the phase change material dwell at 720K to maximize crystal growth. Moreover, the slope of the falling edge of a RESET pulse applied prior to the two-step SET pulse may be adjusted to increase the number of nuclei (e.g., formed with a steeper falling edge) to increase SET efficiency at the expense of a more stable amorphous phase (e.g., formed with a less steep falling edge) that improves data retention.
    Type: Application
    Filed: May 14, 2019
    Publication date: November 19, 2020
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Zhaoqiang Bai, Mac D. Apodaca, Michael K. Grobis, Michael Nicolas Albert Tran, Neil Leslie Robertson, Gerardo A. Bertero
  • Publication number: 20200365204
    Abstract: Systems and methods for improving the crystallization of a phase change material of a phase change memory cell are described. A two-step SET pulse may be applied to the phase change material in which a first lower SET pulse is applied to make the phase change material dwell at 600K to incubate nuclei near the maximum nucleation rate and then a second higher SET pulse is immediately applied to make the phase change material dwell at 720K to maximize crystal growth. Moreover, the slope of the falling edge of a RESET pulse applied prior to the two-step SET pulse may be adjusted to increase the number of nuclei (e.g., formed with a steeper falling edge) to increase SET efficiency at the expense of a more stable amorphous phase (e.g., formed with a less steep falling edge) that improves data retention.
    Type: Application
    Filed: June 26, 2020
    Publication date: November 19, 2020
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Zhaoqiang Bai, Mac D. Apodaca, Michael K. Grobis, Michael Nicolas Albert Tran, Neil Leslie Robertson, Gerardo A. Bertero
  • Patent number: 10839897
    Abstract: Systems and methods for improving the crystallization of a phase change material of a phase change memory cell are described. A two-step SET pulse may be applied to the phase change material in which a first lower SET pulse is applied to make the phase change material dwell at 600K to incubate nuclei near the maximum nucleation rate and then a second higher SET pulse is immediately applied to make the phase change material dwell at 720K to maximize crystal growth. Moreover, the slope of the falling edge of a RESET pulse applied prior to the two-step SET pulse may be adjusted to increase the number of nuclei (e.g., formed with a steeper falling edge) to increase SET efficiency at the expense of a more stable amorphous phase (e.g., formed with a less steep falling edge) that improves data retention.
    Type: Grant
    Filed: May 14, 2019
    Date of Patent: November 17, 2020
    Assignee: SanDisk Technologies LLC
    Inventors: Zhaoqiang Bai, Mac D. Apodaca, Michael K. Grobis, Michael Nicolas Albert Tran, Neil Leslie Robertson, Gerardo A. Bertero
  • Patent number: 10553647
    Abstract: An apparatus is provided that includes a bit line above a substrate, a word line above the substrate, and a non-volatile memory cell between the bit line and the word line. The non-volatile memory cell includes a reversible resistance-switching memory element coupled in series with an isolation element. The isolation element includes a first selector element coupled in series with a second selector element. The first selector element includes a first snapback current, and the second selector element includes a second snapback current lower than the first snapback current.
    Type: Grant
    Filed: June 28, 2018
    Date of Patent: February 4, 2020
    Assignee: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Derek Stewart, Bruce D. Terris
  • Publication number: 20200006432
    Abstract: An apparatus is provided that includes a bit line above a substrate, a word line above the substrate, and a non-volatile memory cell between the bit line and the word line. The non-volatile memory cell includes a reversible resistance-switching memory element coupled in series with an isolation element. The isolation element includes a first selector element coupled in series with a second selector element. The first selector element includes a first snapback current, and the second selector element includes a second snapback current lower than the first snapback current.
    Type: Application
    Filed: June 28, 2018
    Publication date: January 2, 2020
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Michael K. Grobis, Derek Stewart, Bruce D. Terris
  • Patent number: 10355049
    Abstract: An apparatus is provided that includes a bit line above a substrate, a word line above the substrate, and a non-volatile memory cell between the bit line and the word line. The non-volatile memory cell includes a reversible resistance-switching memory element coupled in series with an isolation element. The isolation element includes a first selector element coupled in series with a second selector element.
    Type: Grant
    Filed: June 28, 2018
    Date of Patent: July 16, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Derek Stewart, Bruce D. Terris
  • Patent number: 9251835
    Abstract: A patterned magnetic media having offset servo and data regions. The media can be constructed by a method that allows both a data region and a servo region to be patterned without the patterning of one region adversely affecting the patterning of the other region. The method results in a patterned data region a patterned servo region and intermediate regions between the servo and data regions. The intermediate regions, which are most likely, but not necessarily, asymmetrical with one another indicate that the method has been used to pattern the media.
    Type: Grant
    Filed: June 4, 2013
    Date of Patent: February 2, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Michael K. Grobis, Jeffrey S. Lille, Ricardo Ruiz
  • Patent number: 9087546
    Abstract: In one general embodiment, an apparatus includes a write pole, a near field transducer, a waveguide for delivering light to the near field transducer, and a first heating device positioned between the write pole and at least one of the waveguide and the near field transducer.
    Type: Grant
    Filed: May 6, 2014
    Date of Patent: July 21, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Michael K. Grobis, Lidu Huang, Shen Ren, Hans J. Richter, Erhard Schreck, Barry C. Stipe
  • Patent number: 8922922
    Abstract: A method of storing data in a storage medium includes determining a compensation unit for a portion of the storage medium, reading a first set of bit values from the portion of the storage medium, determining a compensation value based at least in part on an erroneous bit value of the first set of bit values and the compensation unit, and storing the compensation value in association with the portion of the storage medium.
    Type: Grant
    Filed: July 20, 2012
    Date of Patent: December 30, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Michael K. Grobis, Kurt A. Rubin
  • Patent number: 8920948
    Abstract: According to one embodiment, a patterned magnetic storage medium is disclosed herein. The magnetic storage medium includes a pattern formed on a substrate. The pattern includes at least a first and second feature and an edge defined between the first and second features. Additionally, the magnetic storage medium includes a magnetic layer formed on the pattern. The magnetic layer includes grains separated by a non-magnetic segregant boundary. The segregant boundary is positioned above the edge of the pattern.
    Type: Grant
    Filed: December 31, 2011
    Date of Patent: December 30, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Liesl Folks, Michael K. Grobis, Dan S. Kercher, Ricardo Ruiz, Kentaro Takano, Bruce D. Terris, Qing Zhu