Patents by Inventor Tianhong Yan

Tianhong Yan 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: 9543009
    Abstract: Methods for forming non-volatile storage elements in a non-volatile storage system are described. In some embodiments, during a forming operation, a cross-point memory array may be biased such that waste currents are minimized or eliminated. In one example, the memory array may be biased such that a first word line comb is set to a first voltage, a second word line comb interdigitated with the first word line comb is set to the first voltage, and selected vertical bit lines are set to a second voltage such that a forming voltage is applied across non-volatile storage elements to be formed. In some embodiments, a memory array may include a plurality of word line comb layers and a forming operation may be concurrently performed on non-volatile storage elements on all of the plurality of word line comb layers or a subset of the plurality of word line comb layers.
    Type: Grant
    Filed: October 20, 2015
    Date of Patent: January 10, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Chang Siau, Tianhong Yan
  • Publication number: 20170004881
    Abstract: A three-dimensional array especially adapted for memory elements that reversibly change a level of electrical conductance in response to a voltage difference being applied across them. Memory elements are formed across a plurality of planes positioned different distances above a semiconductor substrate. Bit lines to which the memory elements of all planes are connected are oriented vertically from the substrate and through the plurality of planes.
    Type: Application
    Filed: September 1, 2016
    Publication date: January 5, 2017
    Inventors: Tianhong Yan, George Samachisa
  • Patent number: 9484093
    Abstract: Methods for reducing leakage currents through unselected memory cells of a memory array during a memory operation are described. In some cases, the leakage currents through the unselected memory cells of the memory array may be reduced by setting an adjustable resistance bit line structure connected to the unselected memory cells into a non-conducting state. The adjustable resistance bit line structure may comprise a bit line structure in which the resistance of an intrinsic (or near intrinsic) polysilicon portion of the bit line structure may be adjusted via an application of a voltage to a select gate portion of the bit line structure that is not directly connected to the intrinsic polysilicon portion. The intrinsic polysilicon portion may be set into a conducting state or a non-conducting state based on the voltage applied to the select gate portion.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: November 1, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Perumal Ratnam, Christopher Petti, Tianhong Yan
  • Patent number: 9484089
    Abstract: A data storage device includes a memory die and a controller coupled to the memory die. The memory die includes a resistive memory and read/write circuitry configured to determine a first hard bit value and a second hard bit value of a storage element of the resistive memory. The first hard bit value and the second hard bit value are determined using opposite polarity read voltages. The controller is configured to perform error correction with respect to data read from the resistive memory.
    Type: Grant
    Filed: October 20, 2014
    Date of Patent: November 1, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Alexander Bazarsky, Stella Achtenberg, Eran Sharon, Ariel Navon, Idan Alrod, Tz-Yi Liu, Tianhong Yan
  • Patent number: 9472280
    Abstract: Methods for forming non-volatile storage elements in a non-volatile storage system are described. In some embodiments, a plurality of forming operations may be performed in which non-volatile storage elements located near the far end of a plurality of word line fingers associated with a word line comb are formed prior to forming other non-volatile storage elements. In one example, non-volatile storage elements may be formed in each of the plurality of word line fingers in parallel and in an order that forms non-volatile storage elements in each of the plurality of word line fingers that are located near the far ends of the plurality of word line fingers before forming other non-volatile storage elements. Each non-volatile storage element that is formed during a forming operation may be current limited while a forming voltage is applied across the non-volatile storage element.
    Type: Grant
    Filed: June 7, 2015
    Date of Patent: October 18, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Chang Siau, Tianhong Yan
  • Patent number: 9455301
    Abstract: Methods for reducing leakage currents through unselected memory cells of a memory array during a memory operation. In some cases, the leakage currents through the unselected memory cells of the memory array may be reduced by setting an adjustable resistance bit line structure connected to the unselected memory cells into a non-conducting state. The adjustable resistance bit line structure may comprise a bit line structure in which the resistance of an intrinsic (or near intrinsic) polysilicon portion of the bit line structure may be adjusted via an application of a voltage to a select gate portion of the bit line structure that is not directly connected to the intrinsic polysilicon portion. The intrinsic polysilicon portion may be set into a conducting state or a non-conducting state based on the voltage applied to the select gate portion.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: September 27, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Perumal Ratnam, Christopher Petti, Tianhong Yan
  • Patent number: 9442663
    Abstract: Methods for operating a non-volatile memory that includes a plurality of memory arrays in which each memory array of the plurality of memory arrays may independently perform a SET operation, a RESET operation, or a read operation are described. The ability to independently SET or RESET memory arrays allows a SET operation to be performed on a first set of memory cells within a first memory array at the same time as a RESET operation is performed on a second set of memory cells within a second memory array. In some cases, the first memory array may be associated with a first memory bay and the second memory array may be associated with a second memory bay. Each memory bay may include a memory array, read/write circuits, and control circuitry for determining memory cell groupings and programming memory cells within the memory array based on the memory cell groupings.
    Type: Grant
    Filed: November 19, 2014
    Date of Patent: September 13, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Tianhong Yan, Tz-yi Liu
  • Publication number: 20160232969
    Abstract: Independent sense amplifier addressing provides separate column addresses to individual sense amplifier groups within a single bay during one column address cycle. A memory system determines whether the individual memory cells or bits of a column at a bay can be skipped. For each sense amplifier group having at least one memory cell (or bit) that needs to be programmed, the system determines for the first column address whether the memory cell can be skipped. If a bit or memory cell having a first column address from the sense amplifier group can be skipped, the system determines a next bit having a column address from the group that needs to be programmed. The system groups the next column address for programming during the first column address cycle. The system can program a different column address for different sense amplifier groups within the bay during a single column address cycle.
    Type: Application
    Filed: February 11, 2015
    Publication date: August 11, 2016
    Applicant: SANDISK 3D LLC
    Inventors: Gopinath Balakrishnan, Yibo Yin, Tianhong Yan
  • Publication number: 20160217854
    Abstract: A method is provided for reading a memory cell of a nonvolatile memory system. The method includes generating a hard bit and N soft bits for the memory cell in a total time corresponding to a single read latency period and N+1 data transfer times.
    Type: Application
    Filed: March 31, 2016
    Publication date: July 28, 2016
    Applicant: SanDisk Technologies Inc.
    Inventors: Chang Siau, Jeffrey Koon Yee Lee, Tianhong Yan, Yingchang Chen, Gopinath Balakrishnan, Tz-yi Liu
  • Patent number: 9373396
    Abstract: Methods for reducing leakage currents through unselected memory cells of a memory array during a memory operation are described. In some cases, the leakage currents through the unselected memory cells of the memory array may be reduced by setting an adjustable resistance bit line structure connected to the unselected memory cells into a non-conducting state. The adjustable resistance bit line structure may comprise a bit line structure in which the resistance of an intrinsic (or near intrinsic) polysilicon portion of the bit line structure may be adjusted via an application of a voltage to a select gate portion of the bit line structure that is not directly connected to the intrinsic polysilicon portion. The intrinsic polysilicon portion may be set into a conducting state or a non-conducting state based on the voltage applied to the select gate portion.
    Type: Grant
    Filed: May 19, 2015
    Date of Patent: June 21, 2016
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Perumal Ratnam, Christopher Petti, Tianhong Yan
  • Publication number: 20160139828
    Abstract: Methods for operating a non-volatile memory that includes a plurality of memory arrays in which each memory array of the plurality of memory arrays may independently perform a SET operation, a RESET operation, or a read operation are described. The ability to independently SET or RESET memory arrays allows a SET operation to be performed on a first set of memory cells within a first memory array at the same time as a RESET operation is performed on a second set of memory cells within a second memory array. In some cases, the first memory array may be associated with a first memory bay and the second memory array may be associated with a second memory bay. Each memory bay may include a memory array, read/write circuits, and control circuitry for determining memory cell groupings and programming memory cells within the memory array based on the memory cell groupings.
    Type: Application
    Filed: November 19, 2014
    Publication date: May 19, 2016
    Applicant: SANDISK 3D LLC
    Inventors: Tianhong Yan, Tz-yi Liu
  • Publication number: 20160141029
    Abstract: A method of fabricating a resistance-based memory includes initiating formation of a conductive path through a storage element of the resistance-based memory. The method further includes recording data of one or more parameters associated with the formation of the conductive path.
    Type: Application
    Filed: November 19, 2014
    Publication date: May 19, 2016
    Inventors: ARIEL NAVON, IDAN ALROD, ERAN SHARON, IDAN GOLDENBERG, ALEXANDER BAZARSKY, TZ-YI LIU, TIANHONG YAN
  • Publication number: 20160133324
    Abstract: A method includes, in a data storage device including a resistive memory, receiving an erase command to erase a portion of the resistive memory. The method further includes sending shaped data to be stored at the portion of the resistive memory responsive to the erase command.
    Type: Application
    Filed: November 12, 2014
    Publication date: May 12, 2016
    Inventors: IDAN ALROD, NOAM PRESMAN, ARIEL NAVON, TZ-YI LIU, TIANHONG YAN
  • Publication number: 20160133322
    Abstract: A data storage device includes a memory die. The memory die includes a resistive random access memory (ReRAM) having a first portion and a second portion that is adjacent to the first portion. A method includes determining whether to access the second portion of the ReRAM in response to initiating a first operation targeting the first portion of the ReRAM. The method further includes initiating a second operation that senses information stored at the second portion to generate sensed information in response to determining to access the second portion. The method further includes initiating a third operation to rewrite the information at the ReRAM in response to detecting an indication of a disturb condition based on the sensed information.
    Type: Application
    Filed: November 11, 2014
    Publication date: May 12, 2016
    Inventors: Ran ZAMIR, Eran SHARON, Idan ALROD, Ariel NAVON, Tz-Yi LIU, Tianhong YAN
  • Publication number: 20160109926
    Abstract: A data storage device includes a memory die. The memory die includes a resistive memory. A method includes determining a power characteristic associated with performing a write process to write data to the resistive memory. The method further includes initiating a modified write process in response to detecting that the power characteristic satisfies a threshold.
    Type: Application
    Filed: October 20, 2014
    Publication date: April 21, 2016
    Inventors: STELLA ACHTENBERG, IDAN ALROD, ERAN SHARON, ARIEL NAVON, ALEXANDER BAZARSKY, TZ-YI LIU, TIANHONG YAN
  • Publication number: 20160111150
    Abstract: A data storage device includes a memory die and a controller coupled to the memory die. The memory die includes a resistive memory and read/write circuitry configured to determine a first hard bit value and a second hard bit value of a storage element of the resistive memory. The first hard bit value and the second hard bit value are determined using opposite polarity read voltages. The controller is configured to perform error correction with respect to data read from the resistive memory.
    Type: Application
    Filed: October 20, 2014
    Publication date: April 21, 2016
    Inventors: ALEXANDER BAZARSKY, STELLA ACHTENBERG, ERAN SHARON, ARIEL NAVON, IDAN ALROD, TZ-YI LIU, TIANHONG YAN
  • Patent number: 9318194
    Abstract: A method is provided for reading a memory cell of a nonvolatile memory system. The method includes generating a hard bit and N soft bits for the memory cell in a total time corresponding to a single read latency period and N+1 data transfer times.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: April 19, 2016
    Assignee: SanDisk 3D LLC
    Inventors: Chang Siau, Jeffrey Koon Yee Lee, Tianhong Yan, Yingchang Chen, Gopinath Balakrishnan, Tz-yi Liu
  • Patent number: 9312002
    Abstract: A programming technique for a set of resistance-switching memory cells such as ReRAM cell involves programming the low resistance cells to the high resistance state (in a reset process) early in a programming operation, before programming the high resistance cells to the low resistance state (in a set process), to minimize losses due to leakage currents. The reset process can be performed in one or more phases. In some cases, a current limit is imposed which limits the number of cells which can be reset at the same time. Initially, the cells which are to be reset and set are identified by comparing a logical value of their current resistance state to a logical value of write data. If there is a match, the cell is not programmed. If there is not a match, the cell is programmed.
    Type: Grant
    Filed: April 4, 2014
    Date of Patent: April 12, 2016
    Assignee: SanDisk Technologies Inc.
    Inventors: Ariel Navon, Idan Alrod, Eran Sharon, Ishai Ilani, Tz-yi Liu, Tianhong Yan, Gopinath Balakrishnan
  • Publication number: 20160093374
    Abstract: Methods for operating a non-volatile storage system are described. The non-volatile storage system includes a plurality of bit lines, a plurality of word line combs each comprising a plurality of word lines, and a plurality of resistance-switching memory elements. Each resistance-switching memory element is coupled between one of the bit lines and one of the word lines. The method includes calibrating a plurality of bias voltages for the word lines and bit lines based on estimates of data values stored in the resistance-switching memory elements.
    Type: Application
    Filed: September 30, 2014
    Publication date: March 31, 2016
    Inventors: Chang Siau, Tianhong Yan
  • Publication number: 20160093372
    Abstract: A data storage device includes a resistive random access memory (ReRAM). The data storage device includes read circuitry coupled to a storage element of the ReRAM. The read circuitry is configured to read a data value from the storage element, during a read operation, based on a read current sensed during a first phase of the reading operation and a leakage current sensed during a second phase of the reading operation. The data storage device also includes a controller coupled to the read circuitry. The controller is configured to provide an input value to an error correction coding (ECC) decoder, where the input value includes a hard bit value and a soft bit value. The hard bit value corresponds to the data value, and the soft bit value is at least partially based on the leakage current.
    Type: Application
    Filed: September 26, 2014
    Publication date: March 31, 2016
    Inventors: OMER FAINZILBER, ERAN SHARON, IDAN ALROD, ARIEL NAVON, TZ-YI LIU, TIANHONG YAN