Patents by Inventor Mac D. Apodaca

Mac D. Apodaca 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: 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
  • 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
  • Publication number: 20200342926
    Abstract: A memory array is provided that includes a first memory level including a plane of first selector material, and a plurality of first memory cells each including a corresponding first magnetic memory element coupled in series with a corresponding first selector element. Each first selector element includes a region of the plane of first selector material.
    Type: Application
    Filed: April 28, 2019
    Publication date: October 29, 2020
    Applicant: SanDisk Technologies LLC
    Inventors: Jordan A. Katine, Mac D. Apodaca, Christopher J. Petti
  • Patent number: 10586794
    Abstract: The present disclosure generally relates to semiconductor manufactured memory devices and methods of manufacture thereof. More specifically, methods for forming a plurality of layers of a 3D cross-point memory array without the need for lithographic patterning at each layer are disclosed. The method includes depositing a patterned hard mask with a plurality of first trenches over a plurality of layers. Each of the plurality of first trenches is etched all the way through the plurality of layers. Then the hard mask is patterned with a plurality of second trenches, which runs orthogonal to the plurality of first trenches. Selective undercut etching is then used to remove each of the plurality of layers except the orthogonal metal layers from the plurality of second trenches, resulting in a 3D cross-point array with memory material only at the intersections of the orthogonal metal layers.
    Type: Grant
    Filed: June 20, 2017
    Date of Patent: March 10, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Mac D. Apodaca, Daniel Robert Shepard
  • Patent number: 10381408
    Abstract: The present disclosure generally relates to the fabrication of metal-oxide-semiconductor (MOS) select transistors in a vertical orientation such that the transistor pair fits within the footprint of a 4F2 memory cell. The present disclosure further relates to the simultaneous fabrication of a vertical stack of transistors in which each transistor is distinct, as opposed to being serially connected in a NAND-like string. An initial stack of materials is built to include silicon layers to act as source and drain regions as well as to serve as epitaxial growth seed points. As such, the transistor disclosed may be utilized in conjunction with memory elements such as Phase Change, Resistive, or Magnetic RAM memory within array designs, among others.
    Type: Grant
    Filed: March 24, 2016
    Date of Patent: August 13, 2019
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Mac D. Apodaca, Daniel Robert Shepard
  • Patent number: 10290804
    Abstract: Resistive memory cells containing nanoparticles are formed between two electrodes. The nanoparticles may be embedded in a matrix or sintered together without a matrix. The memory cells may be projected memory cells or barrier modulated cells. Polymeric ligands may be used to deposit the nanoparticles over a substrate, followed by an optional removal or replacement of the polymeric ligands.
    Type: Grant
    Filed: June 29, 2017
    Date of Patent: May 14, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ricardo Ruiz, Jeffrey Lille, Mac D. Apodaca, Derek Stewart, Lei Wan, Bruce Terris
  • Patent number: 10283562
    Abstract: A non-volatile storage apparatus is proposed that includes a plurality of serially connected non-volatile reversible resistance-switching memory cells, a plurality of word lines such that each of the memory cells is connected to a different word line, a bit line connected to a first end of the serially connected memory cells and a switch connected to a second end of the serially connected memory cells. In one embodiment, the memory cells include a reversible resistance-switching structure comprising a first material, a second material and a reversible resistance-switching interface between the first material and the second material, a channel, and means for switching current between current flowing through the channel and current flowing through the reversible resistance-switching interface in order to program and read the reversible resistance-switching interface. A process for manufacturing the memory is also disclosed.
    Type: Grant
    Filed: August 23, 2017
    Date of Patent: May 7, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Luiz M. Franca-Neto, Mac D. Apodaca, Christopher J. Petti
  • Patent number: 10249682
    Abstract: A non-volatile storage apparatus is proposed that includes a plurality of serially connected non-volatile reversible resistance-switching memory cells, a plurality of word lines such that each of the memory cells is connected to a different word line, a bit line connected to a first end of the serially connected memory cells and a switch connected to a second end of the serially connected memory cells. In one embodiment, the memory cells include a reversible resistance-switching structure comprising a first material, a second material and a reversible resistance-switching interface between the first material and the second material, a channel, and means for switching current between current flowing through the channel and current flowing through the reversible resistance-switching interface in order to program and read the reversible resistance-switching interface. A process for manufacturing the memory is also disclosed.
    Type: Grant
    Filed: August 23, 2017
    Date of Patent: April 2, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Luiz M. Franca-Neto, Mac D. Apodaca, Christopher J. Petti
  • Patent number: 10249680
    Abstract: A non-volatile memory device that limits the temperature excursion of a selector during operation to enhance the cycling life of the non-volatile memory device. A selector, in line with a memory element, may be degraded with repeated temperature excursions as current passes through a stack during the read/write process. The selector changes from an amorphous state to become crystalline thus reducing the life of a memory device. The memory device includes a word line, a bit line disposed perpendicular to the word line, a stack—including a memory element, a selector, and a spacer—disposed between the word line and bit line, and one or more insulating layers surrounding an outer surface of the stack disposed between the word line and bit line. By surrounding the selector with a high thermal conductive heat-sink material, heat is directed away from the selector helping maintain the selector's amorphous state longer.
    Type: Grant
    Filed: January 19, 2018
    Date of Patent: April 2, 2019
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Mac D. Apodaca, Kurt Allan Rubin
  • Publication number: 20190067374
    Abstract: A non-volatile storage apparatus is proposed that includes a plurality of serially connected non-volatile reversible resistance-switching memory cells, a plurality of word lines such that each of the memory cells is connected to a different word line, a bit line connected to a first end of the serially connected memory cells and a switch connected to a second end of the serially connected memory cells. In one embodiment, the memory cells include a reversible resistance-switching structure comprising a first material, a second material and a reversible resistance-switching interface between the first material and the second material, a channel, and means for switching current between current flowing through the channel and current flowing through the reversible resistance-switching interface in order to program and read the reversible resistance-switching interface. A process for manufacturing the memory is also disclosed.
    Type: Application
    Filed: August 23, 2017
    Publication date: February 28, 2019
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Luiz M. Franca-Neto, Mac D. Apodaca, Christopher J. Petti
  • Publication number: 20190067369
    Abstract: A non-volatile storage apparatus is proposed that includes a plurality of serially connected non-volatile reversible resistance-switching memory cells, a plurality of word lines such that each of the memory cells is connected to a different word line, a bit line connected to a first end of the serially connected memory cells and a switch connected to a second end of the serially connected memory cells. In one embodiment, the memory cells include a reversible resistance-switching structure comprising a first material, a second material and a reversible resistance-switching interface between the first material and the second material, a channel, and means for switching current between current flowing through the channel and current flowing through the reversible resistance-switching interface in order to program and read the reversible resistance-switching interface. A process for manufacturing the memory is also disclosed.
    Type: Application
    Filed: August 23, 2017
    Publication date: February 28, 2019
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Luiz M. Franca-Neto, Mac D. Apodaca, Christopher J. Petti
  • Publication number: 20190066763
    Abstract: Apparatuses, systems, and methods are disclosed for a chip with phase change memory (PCM) and magnetoresistive random access memory (MRAM). An apparatus includes a semiconductor circuit formed over a substrate of a chip. An apparatus includes a PCM array formed over a semiconductor circuit. An apparatus includes an MRAM array formed over a semiconductor circuit.
    Type: Application
    Filed: August 31, 2017
    Publication date: February 28, 2019
    Applicant: SanDisk Technologies LLC
    Inventors: MAC D. APODACA, LUIZ FRANCA-NETO, JORDAN KATINE
  • Publication number: 20190067370
    Abstract: A non-volatile storage apparatus is proposed that includes a plurality of serially connected non-volatile reversible resistance-switching memory cells, a plurality of word lines such that each of the memory cells is connected to a different word line, a bit line connected to a first end of the serially connected memory cells and a switch connected to a second end of the serially connected memory cells. In one embodiment, the memory cells include a reversible resistance-switching structure comprising a first material, a second material and a reversible resistance-switching interface between the first material and the second material, a channel, and means for switching current between current flowing through the channel and current flowing through the reversible resistance-switching interface in order to program and read the reversible resistance-switching interface. A process for manufacturing the memory is also disclosed.
    Type: Application
    Filed: August 23, 2017
    Publication date: February 28, 2019
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Luiz M. Franca-Neto, Mac D. Apodaca, Christopher J. Petti
  • Patent number: 10217795
    Abstract: A non-volatile storage apparatus is proposed that includes a plurality of serially connected non-volatile reversible resistance-switching memory cells, a plurality of word lines such that each of the memory cells is connected to a different word line, a bit line connected to a first end of the serially connected memory cells and a switch connected to a second end of the serially connected memory cells. In one embodiment, the memory cells include a reversible resistance-switching structure comprising a first material, a second material and a reversible resistance-switching interface between the first material and the second material, a channel, and means for switching current between current flowing through the channel and current flowing through the reversible resistance-switching interface in order to program and read the reversible resistance-switching interface. A process for manufacturing the memory is also disclosed.
    Type: Grant
    Filed: August 23, 2017
    Date of Patent: February 26, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Luiz M. Franca-Neto, Mac D. Apodaca, Christopher J. Petti
  • Patent number: 10217505
    Abstract: Apparatuses, systems, and methods are disclosed for a chip with phase change memory (PCM) and magnetoresistive random access memory (MRAM). An apparatus includes a semiconductor circuit formed over a substrate of a chip. An apparatus includes a PCM array formed over a semiconductor circuit. An apparatus includes an MRAM array formed over a semiconductor circuit.
    Type: Grant
    Filed: August 31, 2017
    Date of Patent: February 26, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Mac D. Apodaca, Luiz Franca-Neto, Jordan Katine
  • Patent number: 10147876
    Abstract: Systems and methods for providing a phase change memory that includes a phase change material, such as a chalcogenide material, in series with a heating element that comprises multiple thermal interfaces are described. The multiple thermal interfaces may cause the heating element to have a reduced bulk thermal conductivity or a lower heat transfer rate across the heating element without a corresponding reduction in electrical conductivity. The phase change material may comprise a germanium-antimony-tellurium compound or a chalcogenide glass. The heating element may include a plurality of conducting layers with different thermal conductivities. In some cases, the heating element may include two or more conducting layers in which the conducting layers comprise the same electrically conductive material or compound but are deposited or formed using different temperatures, carrier gas pressures, flow rates, and/or film thicknesses to create thermal interfaces between the two or more conducting layers.
    Type: Grant
    Filed: August 31, 2017
    Date of Patent: December 4, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Lidu Huang, Mac D. Apodaca, Toshiki Hirano, Ailian Zhao, Guy Charles Wicker, Federico Nardi
  • Patent number: 10127979
    Abstract: The present disclosure generally relates to a memory cell and methods for generating a pulse within the memory cell. As such, a geometric arrangement of transistors is disclosed that allows the transistor pulse signal generator circuit to precharge both sides of the memory cell and, subsequently, bring opposite sides of the memory cell quickly to different voltages. The circuit and wiring fabrication provided, when combined with a related transistor manufacturing process, yields pulse generating logic at the memory cell to enable the formation of a well-defined pulse while fitting within the 4F2 footprint of the memory cell. As such, the speed and pulse shape requirements of PCM, MRAM, other such cross-point memory technologies, sensor arrays, and/or pixel displays may take advantage of the reduced RC circuitry delays.
    Type: Grant
    Filed: March 11, 2016
    Date of Patent: November 13, 2018
    Assignee: Western Digital Technologies, Inc.
    Inventors: Mac D. Apodaca, Daniel Robert Shepard
  • Patent number: 10121782
    Abstract: The present disclosure generally relates to semiconductor manufactured memory devices and methods of manufacture thereof. More specifically, methods for forming a plurality of layers of a 3D cross-point memory array without the need for lithographic patterning at each layer are disclosed. The method includes depositing a patterned hard mask with a plurality of first trenches over a plurality of layers. Each of the plurality of first trenches is etched all the way through the plurality of layers. Then the hard mask is patterned with a plurality of second trenches, which runs orthogonal to the plurality of first trenches. Selective undercut etching is then used to remove each of the plurality of layers except the orthogonal metal layers from the plurality of second trenches, resulting in a 3D cross-point array with memory material only at the intersections of the orthogonal metal layers.
    Type: Grant
    Filed: June 21, 2017
    Date of Patent: November 6, 2018
    Assignee: Western Digital Technologies, Inc.
    Inventors: Mac D. Apodaca, Daniel Robert Shepard