Patents Assigned to SanDisk Technologies LLC
  • Patent number: 12205638
    Abstract: Concurrent access of multiple memory cells in a cross-point memory array is disclosed. In one aspect, a forced current approach is used in which, while a select voltage is applied to a selected bit line, an access current is driven separately through each selected word line to concurrently drive the access current separately through each selected memory cell. Hence, multiple memory cells are concurrently accessed. In some aspects, the memory cells are accessed using a self-referenced read (SRR), which improves read margin. Concurrently accessing more than one memory cell in a cross-point memory array improves bandwidth. Moreover, such concurrent accessing allows the memory system to be constructed with fewer, but larger cross-point arrays, which increases array efficiency. Moreover, concurrent access as disclosed herein is compatible with memory cells such as MRAM which require bipolar operation.
    Type: Grant
    Filed: September 7, 2022
    Date of Patent: January 21, 2025
    Assignee: SanDisk Technologies LLC
    Inventors: Nathan Franklin, Ward Parkinson, Michael Grobis, James O'Toole
  • Patent number: 12205640
    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: Grant
    Filed: July 14, 2021
    Date of Patent: January 21, 2025
    Assignee: SanDisk Technologies LLC
    Inventors: Michael K. Grobis, Daniel Bedau, Christopher J. Petti
  • Patent number: 12200932
    Abstract: An alternating stack of insulating layers and spacer material layers is formed over a substrate. An insulating cap layer is formed thereupon. A memory opening is formed, which has a greater lateral dimension at a level of an upper insulating cap sublayer than at a level of a lower insulating cap sublayer. A memory film and a semiconductor channel material layer is formed in the memory opening. Ions of at least one dopant species is implanted into a top portion of the semiconductor channel material layer. An isotropic etch process etches an unimplanted portion of the semiconductor channel material layer at a higher etch rate than the implanted top portion of the semiconductor channel material layer to form a vertical semiconductor channel.
    Type: Grant
    Filed: November 22, 2021
    Date of Patent: January 14, 2025
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Kosaku Yamashita, Yasuaki Yonemochi
  • Patent number: 12197783
    Abstract: A command/address sequence associated with a read/write operation for a memory device that utilizes an existing test data bus in a novel way that obviates the need to utilize an I/O bus for the command/address sequence. As such, the command/address sequence can be performed in parallel with the read/write operations, thereby removing a performance bottleneck that would otherwise be caused by the command and address sequencing. The command/address sequence detects a first enable signal and a data signal on the test data bus and decodes the data signal to obtain at least one of a command latch enable signal and address latch enable signal and at least one of a command code and an address code.
    Type: Grant
    Filed: April 28, 2022
    Date of Patent: January 14, 2025
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Hua-Ling Cynthia Hsu, Fanglin Zhang
  • Patent number: 12191854
    Abstract: Systems and methods for improving the power, performance, and area (PPA) for a voltage mode driver and on die termination (ODT). A voltage mode driver having first and second circuits in a pulldown design. The first circuit has a plurality of nMOS devices in parallel, the plurality of nMOS devices being common to a first resistor. The second circuit is in parallel with the first circuit and has an nMOS device in series with a second resistor. The second circuit is configured to be enabled when the pulldown impedance of the first circuit, with the second circuit disabled and all of the nMOS devices of the first circuit turned on, is greater than a desired pulldown impedance. The voltage mode driver may also be a pullup design, or have both pulldown and pullup stages.
    Type: Grant
    Filed: September 21, 2022
    Date of Patent: January 7, 2025
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Nirav Natwarbhai Patel, Shiv Harit Mathur, Sai Ravi Teja Konakalla
  • Patent number: 12190969
    Abstract: A memory apparatus and operating method are provided. The apparatus includes memory cells connected to word lines and disposed in memory holes and configured to retain a threshold voltage. The memory holes are organized in rows grouped in strings and the strings comprise a plurality of blocks which comprise planes. A control means is configured to program the memory cells connected to one of the word lines and associated with one of the strings in each of the plurality of planes and acquire a smart verify programming voltage individually for each of the planes in a smart verify operation. The control means concurrently programs at least some of the memory cells connected to each of the word lines in each of the planes in a program operation using the smart verify programming voltage individually acquired for each of the planes in the smart verify operation.
    Type: Grant
    Filed: August 25, 2022
    Date of Patent: January 7, 2025
    Assignee: SanDisk Technologies LLC
    Inventors: Ke Zhang, Liang Li
  • Patent number: 12193228
    Abstract: A memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, a memory opening vertically extending through the alternating stack, and a memory opening fill structure located in the memory opening. The memory opening fill structure includes a memory film and a vertical semiconductor channel. The memory film includes a tunneling dielectric layer, a charge storage layer that laterally surrounds the tunneling dielectric layer, a dielectric metal oxide blocking dielectric layer that laterally surrounds the charge storage layer and contacts the vertical semiconductor channel, and a silicon oxide blocking dielectric layer that laterally surrounds the dielectric metal oxide blocking dielectric layer and contacts the vertical semiconductor channel.
    Type: Grant
    Filed: October 7, 2020
    Date of Patent: January 7, 2025
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Noriyuki Nagahata, Takashi Yuda, Ryousuke Itou
  • Patent number: 12185542
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers. Stepped surfaces including vertical sidewalls of the insulating layers are present in a staircase region. Pad stacks are located on the stepped surfaces. Each of the pad stacks includes an insulating pad having a same material composition as the insulating layers, and a dielectric material pad having a different material composition than the insulating layers and having sidewalls that are vertically coincident with sidewalls of the insulating pad. Memory stack structures extend through the alternating stack. Each of the memory stack structures includes a vertical stack of memory elements and a vertical semiconductor channel.
    Type: Grant
    Filed: March 11, 2022
    Date of Patent: December 31, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventor: Kazuto Ohsawa
  • Patent number: 12185540
    Abstract: A method of forming a three-dimensional memory device includes forming an alternating stack of insulating layers and sacrificial material layers over a substrate, forming a memory opening extending through the alternating stack, forming a sacrificial memory opening fill structure in the memory opening, replacing the sacrificial material layers with electrically conductive layers, removing the sacrificial memory opening fill structure selective to the electrically conductive layers, and forming a memory opening fill structure the memory opening after replacing the sacrificial material layers with electrically conductive layers and after removing the sacrificial memory opening fill structure. The memory opening fill structure includes a memory film and a vertical semiconductor channel.
    Type: Grant
    Filed: November 10, 2021
    Date of Patent: December 31, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Michiaki Sano, Yusuke Mukae, Naoki Takeguchi, Yujin Terasawa, Tatsuya Hinoue, Ramy Nashed Bassely Said
  • Patent number: 12176032
    Abstract: Different ramp rates for different regions, or zones, of word lines are used for the pass voltage applied to unselected word lines during a program operation. The properties of the word lines, such as their resistance and capacitance (RC) values, vary across the NAND memory array. By determining the RC values of the word lines across the array, the word lines can be broken into multiple zones based on these properties. The zones can then be individually assigned different ramp rates for applying a pass voltage to the unselected word lines, where a parameter for the ramp rates can be stored as a register value on the memory die.
    Type: Grant
    Filed: August 29, 2022
    Date of Patent: December 24, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Abu Naser Zainuddin, Jiahui Yuan, Towhidur Razzak
  • Patent number: 12176203
    Abstract: A method of depositing a metal includes providing a structure a process chamber, and providing a metal fluoride gas and a growth-suppressant gas into the process chamber to deposit the metal over the structure. The metal may comprise a word line or another conductor of a three-dimensional memory device.
    Type: Grant
    Filed: January 11, 2022
    Date of Patent: December 24, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Fei Zhou, Rahul Sharangpani, Raghuveer S. Makala, Yujin Terasawa, Naoki Takeguchi, Kensuke Yamaguchi, Masaaki Higashitani
  • Patent number: 12176037
    Abstract: In a multi-tiered non-volatile memory structure that can perform operations on sub-blocks, performance of the different tiers/sub-blocks is made consistent by using different word line to word line pitches in the different tiers/sub-blocks.
    Type: Grant
    Filed: September 29, 2022
    Date of Patent: December 24, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Xiang Yang, Wei Cao, Jiacen Guo
  • Patent number: 12178040
    Abstract: A vertically alternating sequence of continuous insulating layers and continuous sacrificial material layers is formed over a substrate, and memory opening fill structures including vertical stacks of memory elements are formed through the vertically alternating sequence. Backside trenches are formed to divide the vertically alternating sequence into a plurality of alternating stacks of insulating layers and sacrificial material layers. A set of one or more bridge structures including a doped semiconductor material is formed within each of the backside trenches. The sacrificial material layers are replaced with electrically conductive layers while the sets of at least one bridge structure are present within the backside trenches.
    Type: Grant
    Filed: August 19, 2021
    Date of Patent: December 24, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ryousuke Itou, Akihisa Sai, Kenzo Iizuka
  • Patent number: 12160989
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers, memory openings vertically extending through the alternating stack, memory opening fill structures located within a respective one of the memory openings, and a drain-select-level isolation structure. One of the insulating layers is a composite insulating layer including an insulating-material-containing sublayer consisting essentially of an insulating material and an etch stop dielectric material sublayer having a material composition that is different from the insulating material. The etch stop dielectric material sublayer can be employed as an etch stop structure during formation of the drain-select-level isolation structure through drain-select-level electrically conductive layers.
    Type: Grant
    Filed: April 8, 2022
    Date of Patent: December 3, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ramy Nashed Bassely Said, Raghuveer S. Makala, Jiahui Yuan, Senaka Kanakamedala
  • Publication number: 20240395328
    Abstract: The nonvolatile memory includes a plurality of nonvolatile memory cells configured to store multiple data states; a word line connected to a control gate of at least one of the plurality of non-volatile memory cells; a control gate line to supply a control gate signal; a word line switch connected between the word line and the control gate line to control the potential applied to the word line from the control gate line; and a memory controller circuit. The memory controller circuit is configured to control a word line potential on the word line and a control gate potential on the control gate line and to control a state of the control gate. The memory controller circuit, when the nonvolatile memory transitions to a not-on state, is further configured to turn off the word line switch and to charge the control gate line to a charged potential.
    Type: Application
    Filed: July 31, 2024
    Publication date: November 28, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Abhijith Prakash, Anubhav Khandelwal
  • Patent number: 12153801
    Abstract: A non-volatile memory system separately performs a memory operation for multiple sub-blocks of a block in order from previously determined slowest sub-block of the block to a previously determined faster sub-block of the block. As a slower sub-block is more likely to fail, this order of is more likely to identify a failure earlier in the process thereby saving time and reducing potential for a disturb. In some embodiments, the proposed order of operation can be used in conjunction with a programming process that concurrently programs blocks in multiple planes using completion of programming of a fastest plane to a data state as a trigger to test for program failure of other planes to the data state.
    Type: Grant
    Filed: November 9, 2022
    Date of Patent: November 26, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Yihang Liu, Xiaochen Zhu, Jie Liu, Sarath Puthenthermadam, Jiahui Yuan, Feng Gao
  • Patent number: 12154630
    Abstract: In order to achieve tight and uniform erased threshold voltage distributions in a non-volatile memory system that includes non-volatile memory cells arranged in blocks that have multiple sub-blocks and has an erase process using gate induced drain leakage (GIDL) to generate charge carriers that change threshold voltage of the memory cells, the magnitude of the GIDL is adjusted separately for the sub-blocks.
    Type: Grant
    Filed: June 3, 2022
    Date of Patent: November 26, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Yi Song, Jiahui Yuan, Yanjie Wang
  • Patent number: 12148489
    Abstract: An apparatus is provided that includes a block including a word line coupled to a plurality of memory cells, and a control circuit coupled to the word line. The control circuit is configured to program the plurality of memory cells by applying program pulses to the word line in a plurality of program loops, determining a first count of a number of the program loops used to complete programming a first subset of the plurality of memory cells to a first programmed state, first comparing the first count to a corresponding first lower limit and a corresponding first upper limit, and determining whether programming the plurality of memory cells has failed based on a result of the first comparing step.
    Type: Grant
    Filed: July 26, 2022
    Date of Patent: November 19, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Yi Song, Sarath Puthenthermadam, Jiahui Yuan
  • Patent number: 12150300
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers containing a terrace region having a plurality of steps, memory stack structures extending through the alternating stack, a retro-stepped dielectric material portion overlying the terrace region, first laterally isolated contact structures including a respective first contact via structure and a respective first dielectric spacer, and second laterally isolated contact structures including a respective second contact via structure and a respective second dielectric spacer. The respective first contact via structure contacts a top surface of a respective first electrically conductive layer in the respective step of the plurality of steps.
    Type: Grant
    Filed: June 10, 2022
    Date of Patent: November 19, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yusuke Tanaka, Haruki Suwa
  • Patent number: 12150302
    Abstract: A memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, a memory opening fill structure including a vertical semiconductor channel and a memory film. The memory film includes a tunneling dielectric layer in contact with the vertical semiconductor channel, a first vertical stack of first dielectric oxide material portions located at levels of the insulating layers and including a dielectric oxide material of a first element, and a second vertical stack of second dielectric oxide material portions located at levels of the electrically conductive layers and including a mixed dielectric oxide material that is a dielectric oxide material of the first element and a second element.
    Type: Grant
    Filed: February 24, 2022
    Date of Patent: November 19, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ramy Nashed Bassely Said, Senaka Kanakamedala, Raghuveer S. Makala, Peng Zhang, Yanli Zhang