Patents by Inventor Changyuan Chen

Changyuan Chen 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: 9201788
    Abstract: In a nonvolatile memory, hybrid blocks are initially written with only lower page data. The hybrid blocks later have middle and upper page data written. For high speed writes, data is written to a hybrid block and two or more Single Level Cell (SLC) blocks. The data from the SLC blocks are copied to the hybrid block at a later time in a folding operation.
    Type: Grant
    Filed: October 22, 2014
    Date of Patent: December 1, 2015
    Assignee: SanDisk Technologies Inc.
    Inventors: Chris Avila, Gautam Dusija, Deepak Raghu, Cynthia Hsu, Changyuan Chen, Farookh Moogat
  • Publication number: 20150331626
    Abstract: In a nonvolatile memory, hybrid blocks are initially written with only lower page data. The hybrid blocks later have middle and upper page data written. For high speed writes, data is written to a hybrid block and two or more Single Level Cell (SLC) blocks. The data from the SLC blocks are copied to the hybrid block at a later time in a folding operation.
    Type: Application
    Filed: October 22, 2014
    Publication date: November 19, 2015
    Inventors: Chris Avila, Gautam Dusija, Deepak Raghu, Cynthia Hsu, Changyuan Chen, Farookh Moogat
  • Publication number: 20140340967
    Abstract: A split gate NAND flash memory structure is formed on a semiconductor substrate of a first conductivity type. The NAND structure comprises a first region of a second conductivity type in the substrate with a second region of the second conductivity type in the substrate, spaced apart from the first region. A continuous first channel region is defined between the first region and the second region. A plurality of floating gates are spaced apart from one another with each positioned over a separate portion of the channel region. A plurality of control gates are provided with each associated with and adjacent to a floating gate. Each control gate has two portions: a first portion over a portion of the channel region and a second portion over the associated floating gate and capacitively coupled thereto.
    Type: Application
    Filed: June 27, 2014
    Publication date: November 20, 2014
    Inventors: Yuniarto Widjaja, John W. Cooksey, Changyuan Chen, Feng Gao, Ya-Fen Lin, Dana Lee
  • Patent number: 8886877
    Abstract: In a nonvolatile memory, hybrid blocks are initially written with only lower page data. The hybrid blocks later have middle and upper page data written. For high speed writes, data is written to a hybrid block and two or more Single Level Cell (SLC) blocks. The data from the SLC blocks are copied to the hybrid block at a later time in a folding operation.
    Type: Grant
    Filed: May 15, 2014
    Date of Patent: November 11, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Chris Avila, Gautam Dusija, Deepak Raghu, Cynthia Hsu, Changyuan Chen, Farookh Moogat
  • Patent number: 8830745
    Abstract: In a programming operation that includes repeated bitscan, program, and verify steps, the bitscan steps may be hidden by performing bitscan in parallel with program preparation and program steps. The effect of a program step may be predicted from previous observation so that when a bitscan indicates that the memory cells are close to being programmed, a last programming step may be completed without subsequent verification or bitscan steps.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: September 9, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Man Lung Mui, Changyuan Chen, Seungpil Lee, Yee Lih Koh, Jongmin Park, Hao Thai Nguyen, Vamsi Krishna Sakhamuri
  • Patent number: 8780642
    Abstract: A split gate NAND flash memory structure is formed on a semiconductor substrate of a first conductivity type. The NAND structure comprises a first region of a second conductivity type in the substrate with a second region of the second conductivity type in the substrate, spaced apart from the first region. A continuous first channel region is defined between the first region and the second region. A plurality of floating gates are spaced apart from one another with each positioned over a separate portion of the channel region. A plurality of control gates are provided with each associated with and adjacent to a floating gate. Each control gate has two portions: a first portion over a portion of the channel region and a second portion over the associated floating gate and capacitively coupled thereto.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: July 15, 2014
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Yuniarto Widjaja, John W. Cooksey, Changyuan Chen, Feng Gao, Ya-Fen Lin, Dana Lee
  • Publication number: 20140022841
    Abstract: In a programming operation that includes repeated bitscan, program, and verify steps, the bitscan steps may be hidden by performing bitscan in parallel with program preparation and program steps. The effect of a program step may be predicted from previous observation so that when a bitscan indicates that the memory cells are close to being programmed, a last programming step may be completed without subsequent verification or bitscan steps.
    Type: Application
    Filed: January 28, 2013
    Publication date: January 23, 2014
    Applicant: SanDisk Technologies Inc.
    Inventors: Man Lung Mui, Changyuan Chen, Seungpil Lee, Yee Lih Koh, Jongmin Park, Hao Thai Nguyen, Vamsi Krishna Sakhamuri
  • Patent number: 8456915
    Abstract: A set of non-volatile storage elements are subjected to a programming process in order to store data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target. Non-volatile storage elements being programmed to a first set of one or more targets are verified to determine whether they have reached their target and are locked out of further programming if it is determined that they have reached their target. Non-volatile storage elements being programmed to the second set of one or more targets are tested to determine the number of fast programming bits. When the number of fast bits for a particular target is greater than a threshold, then programming stops for the non-volatile storage elements being programmed to the particular target.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: June 4, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Changyuan Chen, Jeffrey Lutze, Yingda Dong, Hua-Ling Hsu
  • Publication number: 20120188824
    Abstract: A set of non-volatile storage elements are subjected to a programming process in order to store data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target. Non-volatile storage elements being programmed to a first set of one or more targets are verified to determine whether they have reached their target and are locked out of further programming if it is determined that they have reached their target. Non-volatile storage elements being programmed to the second set of one or more targets are tested to determine the number of fast programming bits. When the number of fast bits for a particular target is greater than a threshold, then programming stops for the non-volatile storage elements being programmed to the particular target.
    Type: Application
    Filed: March 30, 2012
    Publication date: July 26, 2012
    Inventors: Changyuan Chen, Jeffrey Lutze, Yingda Dong, Hua-Ling Hsu
  • Patent number: 8174895
    Abstract: A set of non-volatile storage elements are subjected to a programming process in order to store data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target. Non-volatile storage elements being programmed to a first set of one or more targets are verified to determine whether they have reached their target and are locked out of further programming if it is determined that they have reached their target. Non-volatile storage elements being programmed to the second set of one or more targets are tested to determine the number of fast programming bits. When the number of fast bits for a particular target is greater than a threshold, then programming stops for the non-volatile storage elements being programmed to the particular target.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: May 8, 2012
    Assignee: SanDisk Technologies Inc.
    Inventors: Changyuan Chen, Jeffrey Lutze, Yingda Dong, Hua-Ling Hsu
  • Patent number: 8164135
    Abstract: Nonvolatile flash memory systems and methods are disclosed having a semiconductor substrate of a first conductivity type, including non-diffused channel regions through which electron flow is induced by application of voltage to associated gate elements. A plurality of floating gates are spaced apart from one another and each insulated from the channel region. A plurality of control gates are spaced apart from one another and insulated from the channel region, with each control gate being located between a first floating gate and a second floating gate and capacitively coupled thereto to form a subcell. A plurality of spaced-apart assist gates are insulated from the channel region, with each assist gate being located between and insulated from adjacent subcells. The channel is formed of three regions, two beneath adjacent control gate elements as well as a third region between the first two and beneath an associated assist gate.
    Type: Grant
    Filed: May 4, 2010
    Date of Patent: April 24, 2012
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Changyuan Chen, Ya-Fen Lin, Dana Lee
  • Publication number: 20110170358
    Abstract: A set of non-volatile storage elements are subjected to a programming process in order to store data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target. Non-volatile storage elements being programmed to a first set of one or more targets are verified to determine whether they have reached their target and are locked out of further programming if it is determined that they have reached their target. Non-volatile storage elements being programmed to the second set of one or more targets are tested to determine the number of fast programming bits. When the number of fast bits for a particular target is greater than a threshold, then programming stops for the non-volatile storage elements being programmed to the particular target.
    Type: Application
    Filed: December 15, 2009
    Publication date: July 14, 2011
    Inventors: Changyuan Chen, Jeffrey Lutze, Yingda Dong, Hua-Ling Hsu
  • Patent number: 7961511
    Abstract: A hybrid method of programming a non-volatile memory cell to a final programmed state is described. The method described is a more robust protocol suitable for reliably programming selected memory cells while eliminating programming disturbs. The hybrid method comprises programming the non-volatile memory cell to a first state according to a first coarse programming mechanism, and programming the non-volatile memory cell according to a second different more precise programming mechanism thereby completing the programming of the non-volatile memory cell to the final programmed state. Additionally, the described method is particularly advantageous for programming multilevel chips.
    Type: Grant
    Filed: September 26, 2006
    Date of Patent: June 14, 2011
    Assignee: SanDisk Corporation
    Inventors: Dana Lee, Yingda Dong, Changyuan Chen, Jeffrey Lutze
  • Publication number: 20100322015
    Abstract: A split gate NAND flash memory structure is formed on a semiconductor substrate of a first conductivity type. The NAND structure comprises a first region of a second conductivity type in the substrate with a second region of the second conductivity type in the substrate, spaced apart from the first region. A continuous first channel region is defined between the first region and the second region. A plurality of floating gates are spaced apart from one another with each positioned over a separate portion of the channel region. A plurality of control gates are provided with each associated with and adjacent to a floating gate. Each control gate has two portions: a first portion over a portion of the channel region and a second portion over the associated floating gate and capacitively coupled thereto.
    Type: Application
    Filed: August 31, 2010
    Publication date: December 23, 2010
    Applicant: Silicon Storage Technology, Inc.
    Inventors: Yuniarto Widjaja, John W. Cooksey, Changyuan Chen, Feng Gao, Ya-Fen Lin, Dana Lee
  • Patent number: 7826267
    Abstract: A method and apparatus for dynamic programming and dynamic reading of a select non-volatile memory cell in a virtual grounds array is disclosed. In the dynamic read operation the global bit lines and the associated local bit lines are connected to a precharged voltage. One of the first or second global bit lines is connected to a low voltage such as ground, wherein the one global bit line connected to ground also connects to the local bit line for sensing the select non-volatile memory cell. The state of the select non-volatile memory cell is detected by detecting the sense amplifier connected to the global bit line, other than the one global bit line. In a dynamic programming operation, the first and second global bit lines and their associated local bit lines are precharged to a first voltage. One of the first or second global bit line and its associated local bit lines is connected to a second voltage.
    Type: Grant
    Filed: May 23, 2008
    Date of Patent: November 2, 2010
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Jack Frayer, Ya-Fen Lin, Gianfranco Pellegrini, William Saiki, Changyuan Chen, Xiuhong Chen
  • Patent number: 7808839
    Abstract: A split gate NAND flash memory structure is formed on a semiconductor substrate of a first conductivity type. The NAND structure comprises a first region of a second conductivity type in the substrate with a second region of the second conductivity type in the substrate, spaced apart from the first region. A continuous first channel region is defined between the first region and the second region. A plurality of floating gates are spaced apart from one another with each positioned over a separate portion of the channel region. A plurality of control gates are provided with each associated with and adjacent to a floating gate. Each control gate has two portions: a first portion over a portion of the channel region and a second portion over the associated floating gate and capacitively coupled thereto.
    Type: Grant
    Filed: June 6, 2007
    Date of Patent: October 5, 2010
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Yuniarto Widjaja, John W. Cooksey, Changyuan Chen, Feng Gao, Ya-Fen Lin, Dana Lee
  • Publication number: 20100220533
    Abstract: Nonvolatile flash memory systems and methods are disclosed having a semiconductor substrate of a first conductivity type, including non-diffused channel regions through which electron flow is induced by application of voltage to associated gate elements. A plurality of floating gates are spaced apart from one another and each insulated from the channel region. A plurality of control gates are spaced apart from one another and insulated from the channel region, with each control gate being located between a first floating gate and a second floating gate and capacitively coupled thereto to form a subcell. A plurality of spaced-apart assist gates are insulated from the channel region, with each assist gate being located between and insulated from adjacent subcells. The channel is formed of three regions, two beneath adjacent control gate elements as well as a third region between the first two and beneath an associated assist gate.
    Type: Application
    Filed: May 4, 2010
    Publication date: September 2, 2010
    Inventors: Changyuan Chen, Ya-Fen Lin, Dana Lee
  • Patent number: 7723774
    Abstract: Nonvolatile flash memory systems and methods are disclosed having a semiconductor substrate of a first conductivity type, including non-diffused channel regions through which electron flow is induced by application of voltage to associated gate elements. A plurality of floating gates are spaced apart from one another and each insulated from the channel region. A plurality of control gates are spaced apart from one another and insulated from the channel region, with each control gate being located between a first floating gate and a second floating gate and capacitively coupled thereto to form a subcell. A plurality of spaced-apart assist gates are insulated from the channel region, with each assist gate being located between and insulated from adjacent subcells. The channel is formed of three regions, two beneath adjacent control gate elements as well as a third region between the first two and beneath an associated assist gate.
    Type: Grant
    Filed: July 10, 2007
    Date of Patent: May 25, 2010
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Changyuan Chen, Ya-Fen Lin, Dana Lee
  • Publication number: 20090290430
    Abstract: A method and apparatus for dynamic programming and dynamic reading of a select non-volatile memory cell in a virtual grounds array is disclosed. The array of non-volatile memory cells are arranged in a plurality of rows and columns, wherein each cell in the same column share a first local bit line to one side and share a second local bit line to another side. Alternating local bit lines are connected to a first global bit line and other alternating local bit lines are connected to a second global bit line with the global bit lines connected to a sense amplifier. In the dynamic read operation the global bit lines and the associated local bit lines are connected to a precharged voltage. One of the first or second global bit lines is connected to a low voltage such as ground, wherein the one global bit line connected to ground also connects to the local bit line for sensing the select non-volatile memory cell.
    Type: Application
    Filed: May 23, 2008
    Publication date: November 26, 2009
    Inventors: Jack Frayer, Ya-Fen Lin, Gianfranco Pellegrini, William Saiki, Changyuan Chen, Xiuhong Chen
  • Patent number: 7544569
    Abstract: A split gate NAND flash memory structure is formed on a semiconductor substrate of a first conductivity type. The NAND structure comprises a first region of a second conductivity type and a second region of the second conductivity type in the substrate, spaced apart from the first region, thereby defining a channel region therebetween. A plurality of floating gates are spaced apart from one another and each is insulated from the channel region. A plurality of control gates are spaced apart from one another, with each control gate insulated from the channel region. Each of the control gate is between a pair of floating gates and is capacitively coupled to the pair of floating gates. A plurality of select gates are spaced apart from one another, with each select gate insulated from the channel region. Each select gate is between a pair of floating gates.
    Type: Grant
    Filed: September 5, 2006
    Date of Patent: June 9, 2009
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Feng Gao, Ya-Fen Lin, John W. Cooksey, Changyuan Chen, Yuniarto Widjaja, Dana Lee