Patents by Inventor Xiang Yang

Xiang Yang 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: 20240268115
    Abstract: A memory device includes an alternating stack of insulating layers and electrically conductive layers, a memory opening vertically extending through the alternating stack, a memory opening fill structure located in the memory opening and including a memory film and a vertical semiconductor channel including a first semiconductor material, and source structure including an interfacial source layer and a primary source layer. The interfacial source layer includes a second semiconductor material that has a different band gap from a band gap of the first semiconductor material and is in contact with an end portion of the vertical semiconductor channel. The primary source layer includes a third semiconductor material that has a different band gap from the band gap of the second semiconductor material, and the primary source layer is in contact with the interfacial source layer.
    Type: Application
    Filed: July 24, 2023
    Publication date: August 8, 2024
    Inventors: Wei CAO, Xiang YANG, Koichi MATSUNO
  • Patent number: 12057175
    Abstract: A memory apparatus and method of operation is provided. The apparatus includes memory cells connected to word lines. The memory cells are disposed in memory holes and grouped into a plurality of tiers. The memory cells are configured to retain a threshold voltage corresponding to one of a plurality of data states to store one bit as single-level cells and a plurality of bits as multi-level cells. The apparatus also includes a control means coupled to the word lines and the memory holes and configured to select a predetermined strobe quantity of the plurality of tiers of the memory cells separately for the memory cells operating as the single-level cells and the memory cells operating as the multi-level cells. The control means is also configured to trigger sensing of the predetermined strobe quantity of the plurality of tiers of the memory cells during a verify operation.
    Type: Grant
    Filed: April 7, 2022
    Date of Patent: August 6, 2024
    Inventors: Chin-Yi Chen, Muhammad Masuduzzaman, Kou Tei, Deepanshu Dutta, Hiroyuki Mizukoshi, Jiahui Yuan, Xiang Yang
  • Patent number: 12057166
    Abstract: A memory apparatus and method of operation are provided. The apparatus includes memory cells connected to word lines and arranged in strings. The memory cells are configured to retain a threshold voltage corresponding to memory states. Each one of the strings has drain-side select gate transistors on a drain-side of the one of the strings including top drain-side select gate transistors connected to bit lines and coupled to the memory cells of the-one of the strings. A control means is coupled to the word lines and bit lines and is configured to apply an unselected top voltage to unselected ones of the top drain-side select gate transistors during a memory operation. The control means is also configured to simultaneously apply a selected top voltage to selected ones top drain-side select gate transistors during the memory operation. The unselected top voltage is intentionally different electrically than the selected top voltage.
    Type: Grant
    Filed: September 28, 2021
    Date of Patent: August 6, 2024
    Assignee: SanDisk Technologies LLC
    Inventor: Xiang Yang
  • Patent number: 12045511
    Abstract: The memory device has a plurality of memory blocks including a plurality of memory cells arranged in a plurality of word lines. The memory device also includes control circuitry that is in communication with the plurality of memory blocks. The control circuitry is configured to receive a data write instruction. The control circuitry is further configured to program the memory cells of the memory blocks to an SLC format. In response to the data programmed to the memory cells of the memory blocks in the SLC format reaching an SLC limit prior to completion of the data write instruction, without erasing the memory cells programmed to the SLC format, the control circuitry is configured to program the memory cells of at least some of the plurality of memory blocks from the SLC format to a TLC format.
    Type: Grant
    Filed: August 30, 2022
    Date of Patent: July 23, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Xiang Yang, Wei Cao
  • Patent number: 12046302
    Abstract: A memory apparatus and method of operation are provided. The memory apparatus includes memory cells connected to one of a plurality of word lines including an edge word line and a plurality of other data word lines. The memory cells are disposed in memory holes organized in rows grouped in a plurality of strings. The rows include full circle rows and semi-circle rows. A control means is configured to program the memory cells connected to the edge word line and in the semi-circle rows of a first one and a second one of the plurality of strings to a predetermined one of a plurality of data states in a first program operation. The control means then selects both the first one and the second one of the plurality of strings together and programs the memory cells of the full circle rows together in a second program operation.
    Type: Grant
    Filed: December 21, 2021
    Date of Patent: July 23, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Xiang Yang, Ken Oowada, Deepanshu Dutta
  • Patent number: 12046305
    Abstract: A memory apparatus and method of operation are provided. The apparatus includes memory cells connected to word lines including a dummy word line and other data word lines. The memory cells are disposed in memory holes and configured to retain a threshold voltage. A control means is coupled to the word lines and the memory holes and is configured to determine whether one of the word lines being programmed in a program operation is a particular one of the word lines adjacent the dummy word line needing a dummy positioning operation. The control means is also configured to program the memory cells connected to the dummy word line to adjust the threshold voltage to a predetermined position threshold voltage in the dummy positioning operation in response to determining the one of the plurality of word lines being programmed in the program operation is the particular one of the word lines.
    Type: Grant
    Filed: February 4, 2022
    Date of Patent: July 23, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Xiang Yang, Abhijith Prakash
  • Publication number: 20240212767
    Abstract: The memory device includes a memory block with an array of memory cells arranged word lines. The memory device also includes control circuitry that is configured to program final data into a selected word line in a multi-pass programming operation that includes a first pass and a second pass. In the first pass, the control circuitry is configured to program the memory cells of the selected word line to foggy data and program parity data in the memory device. The parity data includes three possible data states. Prior to the second pass, the control circuitry is configured to read the foggy data and the parity data and reconstruct the final data from the foggy data and the parity data. In the second pass, the control circuitry is configured to program the memory cells of the selected word line from the foggy data to the final data.
    Type: Application
    Filed: July 24, 2023
    Publication date: June 27, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Abhijith Prakash, Xiang Yang
  • Publication number: 20240203511
    Abstract: The memory device includes a memory block with memory cells arranged in word lines that are divided into sub-blocks. Control circuitry is configured to program each of the word lines of a selected sub-blocks in a plurality of program loops. During at least one program loop, the control circuitry applies a programming pulse to a selected word line. The control circuitry is also configured to simultaneously apply a verify voltage to the selected word line and a pass voltage to unselected word lines. In a first phase of a multi-phase pre-charge process, the control circuitry reduces the voltages applied to the selected word line and at least one unprogrammed word line to a low voltage. In a second phase that follows the first phase, the control circuitry reduces the voltages applied to all word lines that remained at the pass voltage to the low voltage.
    Type: Application
    Filed: July 13, 2023
    Publication date: June 20, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Jiacen Guo, Peng Zhang, Xiang Yang, Yanli Zhang
  • Publication number: 20240203506
    Abstract: A non-volatile memory system programs memory cells from an erased threshold voltage distribution to programmed threshold voltage distributions by performing hole pre-charging of channels of unselected NAND strings in a selected block of a selected plane including applying a source voltage to a selected signal line of a plurality of signal lines that are isolated from each other. The selected signal line is positioned between the selected block and an unselected block and is connected to a selected source line of a plurality of source lines that are isolated from each other. The selected source line is connected to the selected block. The source voltage is greater in magnitude than any predetermined threshold voltage of the erased threshold voltage distribution. After the pre-charging, the system boosts channels of unselected NAND strings in the selected block and applies a program voltage to selected NAND strings in the selected block.
    Type: Application
    Filed: July 24, 2023
    Publication date: June 20, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Jiacen Guo, Xiang Yang, Jiahui Yuan
  • Publication number: 20240201882
    Abstract: The present disclosure is related to a programming technique for a memory device that includes a plurality of memory cells arranged in a plurality of word lines. An operating temperature of the memory device is determined. A spike pre-charge voltage is selected based on the operating temperature of the memory device. A first word line and a second word line are programmed in a first programming pass of a multi-pass programming operation. After the first programming pass is completed on the first and second word lines, the first word line is further programmed in a second programming pass that includes a plurality of program loops with pre-charge operations. The spike pre-charge voltage is applied to the second word line during each pre-charge operation.
    Type: Application
    Filed: July 11, 2023
    Publication date: June 20, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Jiacen Guo, Xiang Yang
  • Patent number: 12014785
    Abstract: A memory apparatus and method of operation are provided. The apparatus includes memory cells connected to word lines and arranged in strings. Each of the strings has a drain-side select gate transistor on a drain-side connected to one of a plurality of bit lines. A control means is coupled to the word lines and the plurality of bit lines and the drain-side select gate transistors. The control means determines a unique select gate voltage for each of a plurality of groupings of the memory cells that is individually adapted for each of the plurality of groupings. The control means then applies the unique select gate voltage to the drain-side select gate transistor of selected ones of the strings of each of the plurality of groupings of the memory cells to turn on the drain-side select gate transistor of the selected ones of the strings during a memory operation.
    Type: Grant
    Filed: October 27, 2021
    Date of Patent: June 18, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventor: Xiang Yang
  • Publication number: 20240194278
    Abstract: Technology is disclosed herein for a memory system that includes one or more control circuits configured to connect to a three-dimensional memory structure that includes word lines, with each word line connected to a word line driver at one end. The one or more control circuits are configured to, in a program verify operation, sense memory cells of a first region of a selected word line for a first sense time and sense memory cells of a second region of the selected word line for a second sense time while applying a program-verify voltage to the selected word line. The first region is closer to the word line driver than the second region.
    Type: Application
    Filed: July 27, 2023
    Publication date: June 13, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Jiacen Guo, Xiang Yang
  • Publication number: 20240192873
    Abstract: A storage device is disclosed herein. The storage device comprises a non-volatile memory, where the non-volatile memory includes a block of 3N wordlines partitioned into a plurality of sub-blocks. The plurality of sub-blocks include an upper sub-block of a first subset of the block of 3N wordlines, a lower sub-block of a second subset of the block of 3N wordlines, and a middle sub-block of a third subset of the block of 3N wordlines. Further, the storage device comprises control circuitry coupled to the block of 3N wordlines and configured to: perform a program operation in a normal order programming sequence on the upper sub-block; perform a program operation in a reverse order programming sequence on the lower sub-block; and perform a program operation in the reverse order programming sequence on the middle sub-block.
    Type: Application
    Filed: July 11, 2023
    Publication date: June 13, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Xiang Yang, Wei Cao, Jiacen Guo
  • Publication number: 20240194277
    Abstract: Technology is disclosed herein for a memory system that includes control circuits that are configured to connect to a three-dimensional memory structure. The memory structure includes NAND strings arranged in a plurality of rows, a plurality of bit lines connected to the NAND strings and a plurality of word lines, each word line coupled to the plurality of rows of NAND strings. The control circuits are configured to, in a program-verify operation, sense memory cells of a first row of NAND strings coupled to the selected word line for a first sense time and sense memory cells of a second row of NAND strings coupled to the selected word line for a second sense time while applying a program-verify voltage to the selected word line.
    Type: Application
    Filed: July 27, 2023
    Publication date: June 13, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Jiacen Guo, Xiang Yang, Yi Song, Jiahui Yuan
  • Publication number: 20240185928
    Abstract: A method for performing a read operation of a fully programmed non-volatile memory that, initially, was partially programmed, the method comprising: selecting a word line within an initially programmed portion; applying a read to the selected word line, determining a first “optimal” read verify voltage level for each program state; once fully programmed, applying a read to the selected word line, determining a second “optimal” read verify voltage level for each program state; for each program state, determining a difference between the first “optimal” read verify voltage level and the second “optimal” read verify voltage level, the difference defining a supplemental offset value; determining an “optimal” read verify voltage level for each program state by applying the supplemental offset value in conjunction with an initial offset value defined in a pre-calibrated “lookup” table; and applying a read to each word line according to each determined “optimal” read verify voltage level.
    Type: Application
    Filed: July 7, 2023
    Publication date: June 6, 2024
    Applicant: Western Digital Technologies, Inc.
    Inventors: Abhijith Prakash, Xiang Yang
  • Publication number: 20240184468
    Abstract: A memory apparatus and method of operation are provided. The apparatus includes memory cells each connected to one of a plurality of word lines and disposed in memory holes. The memory cells are configured to retain a threshold voltage corresponding to one of a plurality of data states. A control means is coupled to the plurality of word lines and the memory holes and is configured to identify at least one grouping of the memory cells to be programmed with a multi-pass programming operation. The control means is also configured to program the at least one grouping of the memory cells using the multi-pass programming operation. The control means is additionally configured to program the memory cells other than the at least one grouping of the memory cells in a full sequence programming operation.
    Type: Application
    Filed: July 20, 2023
    Publication date: June 6, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Wei Cao, Xiang Yang
  • Patent number: 11990185
    Abstract: Technology is disclosed herein reconfiguring word lines as either data word lines or dummy word lines. In a sub-block mode reconfigurable word lines are used as dummy word lines that provide electrical isolation between data word lines in a block. The block may be divided into an upper tier, a middle tier, and a lower tier, with the reconfigurable word lines within the middle tier. In a full-block mode the reconfigurable group of the word lines are used as data word lines. Because the reconfigurable word lines are used as data word lines in the full-block mode storage capacity is greater in the full-block mode than in the sub-block mode. Moreover, because the sub-blocks are smaller in size but greater in number than the full-blocks, the memory system may be provisioned with fewer blocks and still meet user storage requirements in both the full-block mode and the sub-block mode.
    Type: Grant
    Filed: August 15, 2022
    Date of Patent: May 21, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Xiang Yang, YenLung Li, James Kai
  • Publication number: 20240161828
    Abstract: A non-volatile memory includes a plurality of non-volatile memory cells arranged in blocks. Each block includes multiple sub-blocks that can be independently erased and programmed. A control circuit is connected to the non-volatile memory cells. The control circuit is configured to independently erase and program sub-blocks of a same block. The control circuit is configured to only allow one sub-block per block to be open at a time.
    Type: Application
    Filed: July 24, 2023
    Publication date: May 16, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Xiang Yang, Wei Cao, Jiacen Guo
  • Patent number: 11972818
    Abstract: A memory apparatus and method of operation are provided. The apparatus includes memory cells each connected to word lines. The memory cells are disposed in strings and configured to retain a threshold voltage corresponding to data states. A control means is configured to apply verification pulses of program verify voltages each associated with one of the data states to selected ones of the word lines to determine whether the memory cells connected thereto have the threshold voltage above each of the program verify voltages targeted for each of the memory cells during a program-verify portion of a program operation. The control means is also configured to trim the program verify voltages for each of the data states for a grouping of the memory cells based on quantities of the memory cells having the threshold voltage crossing over between the data states in crossovers in a verify level trimming process.
    Type: Grant
    Filed: June 15, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Abhijith Prakash, Xiang Yang
  • Patent number: D1024766
    Type: Grant
    Filed: June 28, 2022
    Date of Patent: April 30, 2024
    Inventor: Gui Xiang Yang