Patents Assigned to SanDisk Technologies LLC
  • Patent number: 11978516
    Abstract: A memory system having a dynamic supply voltage to sense amplifiers. The supply voltage has a higher magnitude when charging inhibited bit lines during a program operation and a lower magnitude when verifying/sensing memory cells. Reducing the magnitude of the supply voltage saves power and/or current. However, if the lower magnitude were used when the inhibited bit lines are charged during the program operations, some of the memory cells that should be inhibited from programming might experience at least some programming. Using the higher magnitude supply voltage during bit line charging of the program operation assures that the inhibited bit lines are charged to a sufficient voltage to keep drain side select gates of NAND strings off so that the NAND channel will boost properly to inhibit programming of such memory cells.
    Type: Grant
    Filed: April 11, 2022
    Date of Patent: May 7, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Yanjie Wang, Ohwon Kwon, Kou Tei, Tai-Yuan Tseng, Yasue Yamamoto, Yonggang Wu, Guirong Liang
  • Patent number: 11978491
    Abstract: Technology for reading reversible resistivity cells in a memory array when using a current-force read is disclosed. The memory cells are first read using a current-force referenced read. If the current-force referenced read is successful, then results of the current-force referenced read are returned. If the current-force referenced read is unsuccessful, then a current-force self-referenced read (SRR) is performed and results of the current-force SRR are returned. In an aspect this mixed current-force read is used for MRAM cells, which are especially challenging to read.
    Type: Grant
    Filed: September 24, 2021
    Date of Patent: May 7, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Michael Nicolas Albert Tran, Ward Parkinson, Michael Grobis, Nathan Franklin, Raj Ramanujan
  • Patent number: 11978774
    Abstract: A field effect transistor for a high voltage operation can include vertical current paths, which may include vertical surface regions of a pedestal semiconductor portion that protrudes above a base semiconductor portion. The pedestal semiconductor portion can be formed by etching a semiconductor material layer employing a gate structure as an etch mask. A dielectric gate spacer can be formed on sidewalls of the pedestal semiconductor portion. A source region and a drain region may be formed underneath top surfaces of the base semiconductor portion. Alternatively, epitaxial semiconductor material portions can be grown on the top surfaces of the base semiconductor portions, and a source region and a drain region can be formed therein. Alternatively, a source region and a drain region can be formed within via cavities in a planarization dielectric layer.
    Type: Grant
    Filed: October 5, 2020
    Date of Patent: May 7, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventor: Mitsuhiro Togo
  • Publication number: 20240143229
    Abstract: An apparatus includes a control circuit configured connect to non-volatile memory cells. The control circuit is configured to receive a read command directed to data stored in non-volatile memory cells of a first word line and determine that a second word line adjacent to the first word line is sanitized. The control circuit is further configured to select an adjusted read voltage for a read operation directed to the non-volatile memory cells of the first word line based on the determination.
    Type: Application
    Filed: July 27, 2023
    Publication date: May 2, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Md Raquibuzzaman, Sujjatul Islam, Ravi J. Kumar
  • Publication number: 20240144002
    Abstract: A system that includes a machine learning model that is configured to receive an input layout file that includes a portion of an integrated circuit layout that has a previously identified wafer hotspot, match the previously identified wafer hotspot to one of a plurality of categories of wafer hotspot types, and output a proposed layout modification associated with the matching category of wafer hotspot types.
    Type: Application
    Filed: July 19, 2023
    Publication date: May 2, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Chen-Che Huang, Lauren Matsumoto, Chunming Wang
  • Publication number: 20240145006
    Abstract: Memory cells of a second sub-block are programmed by pre-charging channels of unselected memory cells connected to the selected word line, boosting the pre-charged channels of unselected memory cells and applying a program voltage to selected non-volatile memory cells connected to the selected word line. The pre-charging includes applying one or more overdrive voltages to word lines connected to memory cells of a first sub-block to provide a conductive path from memory cells of the second sub-block through the first sub-block to a source line and maintaining the word lines connected to memory cells of the first sub-block at one or more overdrive voltages while ramping down signals at the end of the pre-charging. Dummy word lines, positioned between sub-blocks, are maintained at a resting voltage during the boosting in order to cut-off channels of memory cells in the second sub-block from channels of memory cells in the first sub-block.
    Type: Application
    Filed: July 24, 2023
    Publication date: May 2, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Peng Zhang, Yanli Zhang, Dengtao Zhao, Jiacen Guo
  • Patent number: 11972804
    Abstract: The memory device includes a memory block with an array of memory cells. The memory device also includes control circuitry that is in communication with the memory cells. The control circuitry is configured to program a group of the memory cells in a programming operation that does not include verify to obtain a natural threshold voltage (nVt) distribution, calculate an nVt width of the nVt distribution, compare the nVt width to a threshold, and identify the memory block as being vulnerable to cross-temperature read errors in response to the nVt width exceeding the threshold.
    Type: Grant
    Filed: June 22, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Xuan Tian, Henry Chin, Liang Li, Vincent Yin, Wei Zhao, Tony Zou
  • Patent number: 11972805
    Abstract: In a non-volatile memory, to achieve a shallow and tight erased threshold voltage distribution, a process is performed that includes erasing a group of non-volatile memory cells, identifying a first set of the bit lines that are connected to non-volatile memory cells of the group that are erased past a lower limit for erased non-volatile memory cells and identifying a second set of the bit lines that are connected to non-volatile memory cells of the group that are not erased past the lower limit for erased non-volatile memory cells, and applying programming to non-volatile memory cells connected to the first set of bit lines while inhibiting programming for non-volatile memory cells connected to the second set of bit lines.
    Type: Grant
    Filed: August 5, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: Yi Song, Yanjie Wang, Jiahui Yuan
  • Patent number: 11973123
    Abstract: A semiconductor structure includes an active region including a source region, a drain region, and a channel region extending between the source region and the drain region, a gate stack, and a gate dielectric layer located between the gate stack and the active region. The gate stack includes an electrically conductive gate electrode and a single crystalline III-nitride ferroelectric plate located between the electrically conductive gate electrode and the gate dielectric layer, and an entirety of the single crystalline III-nitride ferroelectric plate is single crystalline.
    Type: Grant
    Filed: January 18, 2022
    Date of Patent: April 30, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Adarsh Rajashekhar, Raghuveer S. Makala, Kartik Sondhi
  • Patent number: 11971736
    Abstract: A circuit is provided that includes a first transistor having a first terminal, a second terminal and a third terminal, and a second transistor comprising a first terminal, a second terminal and a third terminal. The first terminal of the first transistor comprises an input terminal of the circuit, the second terminal of the first transistor is coupled to a power supply bus, and the first transistor conducts a first current. The first terminal of the first transistor comprises an output terminal of the circuit, the second terminal of the second transistor is coupled to the power supply bus, and the third terminal of the second transistor is coupled to the third terminal of the first transistor. The second transistor conducts a second current proportional to the first current substantially independent of distance between the first transistor and the second transistor.
    Type: Grant
    Filed: February 16, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies LLC
    Inventors: James O'Toole, Ward Parkinson, Thomas Trent
  • Patent number: 11972810
    Abstract: A memory apparatus and method of operation are provided. The apparatus includes memory cells connected word lines. The memory cells are disposed in strings and configured to retain a threshold voltage. A control means is configured to apply a program voltage to selected ones of the word lines while applying pass voltages to unselected ones of the word lines and ramp down both the selected ones of the plurality of word lines and the unselected ones of the word lines to a recovery voltage at a start of a verify phase of each of a plurality of program loops and apply a targeted word line bias to each of the word lines during the verify phase. The control means is also configured to adjust the recovery voltage based on the targeted word line bias applied to each of the plurality of word lines during the verify phase.
    Type: Grant
    Filed: June 21, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Han-Ping Chen, Wei Zhao, Henry Chin
  • Patent number: 11972801
    Abstract: A non-volatile semiconductor memory device, described herein, comprises non-volatile storage elements and one or more control circuits in communication with the non-volatile storage elements. The one or more control circuits are configured to, during a program iteration of a program operation, determine whether a program voltage level of the program iteration exceeds a threshold program voltage level and in response to the determination, identify a set of voltage levels to apply to a source line connected to a set of the non-volatile storage elements. The one or more control circuits are further configured to perform the program iteration of the program operation on the set of non-volatile storage elements, where the program iteration includes applying the set of voltage levels to the source line.
    Type: Grant
    Filed: February 7, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Xue Pitner, Yu-Chung Lien, Sarath Puthenthermadam, Sujjatul Islam
  • Patent number: 11972954
    Abstract: An alternating stack of first material layers and second material layers can be formed over a semiconductor material layer. A patterning film is formed over the alternating stack, and openings are formed through the patterning film. Via openings are formed through the alternating stack at least to a top surface of the semiconductor material layer by performing a first anisotropic etch process that transfers a pattern of the openings in the patterning film. A cladding liner can be formed on a top surface of the patterning film and sidewalls of the openings in the pattering film. The via openings can be vertically extended through the semiconductor material layer at least to a bottom surface of the semiconductor material layer by performing a second anisotropic etch process employing the cladding liner as an etch mask.
    Type: Grant
    Filed: June 23, 2021
    Date of Patent: April 30, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Roshan Jayakhar Tirukkonda, Senaka Kanakamedala, Rahul Sharangpani, Raghuveer S. Makala, Monica Titus
  • Patent number: 11972806
    Abstract: The memory device includes a memory block with a plurality of memory cells, which are programmed to multiple bits per memory cell, arranged in a plurality of word lines. Control circuitry is provided and is configured to read the memory cells of a selected word line. The control circuitry separates the memory cells of the selected word line into a first group of memory cells, which are located on a side of the word line are near a voltage driver, and a second group of memory cells, which are located on an opposite side of the word line from the voltage driver. The control circuitry reads the memory cells of the first group using a first read mode and reads the memory cells of the second group using a second read mode that is different than the first read mode to reduce a fail bit count during read.
    Type: Grant
    Filed: June 10, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Jiacen Guo, Xiang Yang
  • Patent number: 11972813
    Abstract: A memory device with adaptive sense time tables is disclosed. In order to maintain a desired (initial or preset) threshold voltage distribution, the sense time is adjusted as the program-erase cycle count increases. The program-erase cycle process tends to wear down memory cells, causing the QPW window to expand and the threshold voltage to widen. However, by adjusting (i.e., reducing) the sense time for increased program-erase cycles, the QPW window and the threshold voltage can be at least substantially maintained. Additionally, systems and methods for adjusting sense time based on die-to-die variations are also disclosed.
    Type: Grant
    Filed: December 20, 2021
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Jiacen Guo, Xiang Yang, Swaroop Kaza, Laidong Wang
  • Patent number: 11972807
    Abstract: Technology is disclosed herein for a memory system that regulates charge pump current during a ramp up of the output voltage. The memory systems operates the charge pump in a current regulation mode while the charge pump output voltage ramps up. After the output voltage crosses a threshold voltage, the charge pump is operated in a voltage regulation mode in which the output voltage is regulated to a target output voltage. In one aspect, the memory system generates a random duty cycle clock in the current regulation mode. The memory system determines a target duty cycle for the random duty cycle clock that will regulate the input current of the charge pump to a target current, given the present output voltage. A clock based on the random duty cycle clock is provided to a clock input of the charge pump to regulate the charge pump current.
    Type: Grant
    Filed: May 11, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies LLC
    Inventor: Hiroki Yabe
  • 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: 11972808
    Abstract: A memory apparatus and method of operation are provided. The apparatus includes memory cells connected to word lines and disposed in memory holes organized in rows grouped in strings and configured to retain a threshold voltage. The memory cells are connected in series between a drain-side select gate transistor on a drain-side of each of the memory holes and a source-side select gate transistor on a source-side of each of the memory holes. A control means determines whether a downshift recovery trigger event has occurred in memory operations. In response to determining the downshift recovery trigger event has occurred, the control means inserts at least one of a predetermined idle time in the memory operations and a recovery pulse of a negative voltage to the drain-side select gate transistor of the memory holes of the strings for a predetermined pulse period of time during one of the memory operations.
    Type: Grant
    Filed: February 8, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Abhijith Prakash, Xiang Yang
  • Patent number: 11972814
    Abstract: The memory device includes a plurality of memory cells, which include a first set of memory cells and a second set of memory cells. A controller is in communication with the memory cells. The controller is configured to, in a first programming pass and then a second programming pass, program the memory cells of the first and second sets to respective final threshold voltages associated with a plurality of programmed data states. The controller is further configured to, in the first programming pass, verify the first set of memory cells at a first set of checkpoint data states and verify the second set of memory cells at a second set of checkpoint data states that is different than the first set of checkpoint data states.
    Type: Grant
    Filed: March 22, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Xue Bai Pitner, Yu-Chung Lien, Ravi Kumar, Jiahui Yuan, Bo Lei, Zhenni Wan
  • Patent number: 11972803
    Abstract: A memory device that uses different programming parameters base on the word line(s) to be programmed is described. The programming parameter PROGSRC_PCH provides a pre-charge voltage to physical word lines. In some instances, the PROGSRC_PCH voltage is decoupled, and a new PROGSRC_PCH represents an adjusted (e.g., increased) pre-charge voltage for a certain physical word line or word line zone (i.e., predetermined group of word lines). Using different PROGSRC_PCH voltages can limit or prevent Vt distribution window degradation, particularly for relatively low physical word lines. Additionally, the overall programming time and average current consumed can also be reduced.
    Type: Grant
    Filed: January 7, 2022
    Date of Patent: April 30, 2024
    Assignee: SanDisk Technologies, LLC
    Inventors: Yu-Chung Lien, Fanqi Wu, Jiahui Yuan