Patents by Inventor Teruhiko Kamei

Teruhiko Kamei 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: 9202581
    Abstract: A sensing method for a flash memory to improve read time of separate sensing in each bit line pair is introduced herein. The sensing method improves read time of even/odd BL separate sensing by, for example, charge time saving for sensing each of the bit lines during reading. In the method, both of the even bit line and the odd bit line are charged to a charge level. The voltage level of the odd bit line is maintained at the charge level and memory cells associated with the even bit line are sensed for reading data stored in the memory cells. The voltage level of the even bit line is discharged to ground, and the voltage level of the odd bit line is maintained at the charge level and sensed for reading data stored in the memory cells associated with the odd bit line.
    Type: Grant
    Filed: September 25, 2014
    Date of Patent: December 1, 2015
    Assignee: MACRONIX International Co., Ltd.
    Inventor: Teruhiko Kamei
  • Patent number: 9053819
    Abstract: A non-volatile storage system that performs a multi-stage programming process to program non-volatile storage to a set of data threshold voltage distributions. The multi-stage programming process includes performing a first stage of the multi-stage programming process to change threshold voltages of at least a subset of the non-volatile storage elements from an erased distribution to one or more intermediate distributions, performing an intermediate stage of the multi-stage programming process to change threshold voltages of at least some of the non-volatile storage elements to appropriate distributions of the data threshold voltage distributions, and performing a later stage of the multi-stage programming process, after performing the intermediate stage of the multi-stage programming process, to tighten only a subset of the data threshold voltage distributions.
    Type: Grant
    Filed: July 11, 2012
    Date of Patent: June 9, 2015
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Teruhiko Kamei, Cuong Trinh, Atsushi Inoue, Toshiyuki Takahashi
  • Patent number: 9047954
    Abstract: Methods for compensating for variations in bit line resistance during sensing of memory cells are described. The variations in bit line resistance may occur die-to-die or plane-to-plane on the same die. In some embodiments, for each die or memory plane on a die, a plurality of bit line read voltages associated with a plurality of zones may be determined based on sensing criteria. The sensing criteria may comprise a number of fail bits. Each zone of the plurality of zones may be associated with a memory array region within a die or memory plane. Prior to performing a read or verify operation on a group of memory cells, a bit line read voltage used during sensing of the group of memory cells may be determined based on the plurality of bit line read voltages and a zone associated with the group of memory cells.
    Type: Grant
    Filed: April 19, 2014
    Date of Patent: June 2, 2015
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Teruhiko Kamei, Seungpil Lee, Siu Lung Chan, Kwang Ho Kim, Man Lung Mui
  • Patent number: 8942047
    Abstract: Upon selecting non-volatile storage elements to be sensed, the system obtains information about the position of these non-volatile storage elements, determines sensing parameters based at least in part on this information, pre-charges a charge storage device and, while maintaining the voltage level of the bit lines of these memory cells at a constant value, applies a reference signal to these non-volatile storage elements for a certain duration of time, afterwards determining whether, for the certain duration of time, the current conducted by these non-volatile storage elements exceeds a predetermined value.
    Type: Grant
    Filed: May 29, 2014
    Date of Patent: January 27, 2015
    Assignee: Sandisk Technologies Inc.
    Inventors: Man L. Mui, Teruhiko Kamei, Yingda Dong, Ken Oowada, Yosuke Kato, Fumitoshi Ito, Seungpil Lee
  • Patent number: 8908432
    Abstract: Methods for compensating for variations in bit line resistance during sensing of memory cells are described. The variations in bit line resistance may occur die-to-die or plane-to-plane on the same die. In some embodiments, for each die or memory plane on a die, a plurality of bit line read voltages associated with a plurality of zones may be determined based on sensing criteria such as a number of fail bits. Each zone of the plurality of zones may be associated with a memory array region within a memory plane. Within each zone, different bit line read voltages may be applied to different bit line groupings in order to compensate for systematic variations in bit line resistance between neighboring bit lines due to the use of multiple patterning lithography techniques such as spacer-based double patterning.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: December 9, 2014
    Assignee: Sandisk Technologies, Inc.
    Inventors: Teruhiko Kamei, Seungpil Lee, Siu Lung Chan, Kwang Ho Kim, Man Lung Mui
  • Patent number: 8885416
    Abstract: Upon selecting non-volatile storage elements to be sensed, the system obtains information about the position of these non-volatile storage elements, determines sensing parameters based at least in part on this information, pre-charges a charge storage device and, while maintaining the voltage level of the bit lines of these memory cells at a constant value, applies a reference signal to these non-volatile storage elements for a certain duration of time, afterwards determining whether, for the certain duration of time, the current conducted by these non-volatile storage elements exceeds a predetermined value.
    Type: Grant
    Filed: January 30, 2013
    Date of Patent: November 11, 2014
    Assignee: Sandisk Technologies Inc.
    Inventors: Man L. Mui, Teruhiko Kamei, Yingda Dong, Ken Oowada, Yosuke Kato, Fumitoshi Ito, Seungpil Lee
  • Publication number: 20140269083
    Abstract: Upon selecting non-volatile storage elements to be sensed, the system obtains information about the position of these non-volatile storage elements, determines sensing parameters based at least in part on this information, pre-charges a charge storage device and, while maintaining the voltage level of the bit lines of these memory cells at a constant value, applies a reference signal to these non-volatile storage elements for a certain duration of time, afterwards determining whether, for the certain duration of time, the current conducted by these non-volatile storage elements exceeds a predetermined value.
    Type: Application
    Filed: May 29, 2014
    Publication date: September 18, 2014
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Man L. Mui, Teruhiko Kamei, Yingda Dong, Ken Oowada, Yosuke Kato, Fumitoshi Ito, Seungpil Lee
  • Publication number: 20140226405
    Abstract: Methods for compensating for variations in bit line resistance during sensing of memory cells are described. The variations in bit line resistance may occur die-to-die or plane-to-plane on the same die. In some embodiments, for each die or memory plane on a die, a plurality of bit line read voltages associated with a plurality of zones may be determined based on sensing criteria. The sensing criteria may comprise a number of fail bits. Each zone of the plurality of zones may be associated with a memory array region within a die or memory plane. Prior to performing a read or verify operation on a group of memory cells, a bit line read voltage used during sensing of the group of memory cells may be determined based on the plurality of bit line read voltages and a zone associated with the group of memory cells.
    Type: Application
    Filed: April 19, 2014
    Publication date: August 14, 2014
    Applicant: SANDISK TECHNOLOGIES, INC.
    Inventors: Teruhiko Kamei, Seungpil Lee, Siu Lung Chan, Kwang Ho Kim, Man Lung Mui
  • Publication number: 20140211568
    Abstract: Upon selecting non-volatile storage elements to be sensed, the system obtains information about the position of these non-volatile storage elements, determines sensing parameters based at least in part on this information, pre-charges a charge storage device and, while maintaining the voltage level of the bit lines of these memory cells at a constant value, applies a reference signal to these non-volatile storage elements for a certain duration of time, afterwards determining whether, for the certain duration of time, the current conducted by these non-volatile storage elements exceeds a predetermined value.
    Type: Application
    Filed: January 30, 2013
    Publication date: July 31, 2014
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Man L. Mui, Teruhiko Kamei, Yingda Dong, Ken Oowada, Yosuke Kato, Fumitoshi Ito, Seungpil Lee
  • Patent number: 8743618
    Abstract: Methods for compensating for variations in bit line resistance during sensing of memory cells are described. The variations in bit line resistance may occur die-to-die or plane-to-plane on the same die. In some embodiments, for each die or memory plane on a die, a plurality of bit line read voltages associated with a plurality of zones may be determined based on sensing criteria. The sensing criteria may comprise a number of fail bits. Each zone of the plurality of zones may be associated with a memory array region within a die or memory plane. Prior to performing a read or verify operation on a group of memory cells, a bit line read voltage used during sensing of the group of memory cells may be determined based on the plurality of bit line read voltages and a zone associated with the group of memory cells.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: June 3, 2014
    Assignee: Sandisk Technologies Inc.
    Inventors: Teruhiko Kamei, Seungpil Lee, Siu Lung Chan, Kwang Ho Kim, Man Lung Mui
  • Publication number: 20140133230
    Abstract: Methods for compensating for variations in bit line resistance during sensing of memory cells are described. The variations in bit line resistance may occur die-to-die or plane-to-plane on the same die. In some embodiments, for each die or memory plane on a die, a plurality of bit line read voltages associated with a plurality of zones may be determined based on sensing criteria such as a number of fail bits. Each zone of the plurality of zones may be associated with a memory array region within a memory plane. Within each zone, different bit line read voltages may be applied to different bit line groupings in order to compensate for systematic variations in bit line resistance between neighboring bit lines due to the use of multiple patterning lithography techniques such as spacer-based double patterning.
    Type: Application
    Filed: January 31, 2013
    Publication date: May 15, 2014
    Applicant: SANDISK TECHNOLOGIES, INC.
    Inventors: Teruhiko Kamei, Seungpil Lee, Siu Lung Chan, Kwang Ho Kim, Man Lung Mui
  • Publication number: 20140133229
    Abstract: Methods for compensating for variations in bit line resistance during sensing of memory cells are described. The variations in bit line resistance may occur die-to-die or plane-to-plane on the same die. In some embodiments, for each die or memory plane on a die, a plurality of bit line read voltages associated with a plurality of zones may be determined based on sensing criteria. The sensing criteria may comprise a number of fail bits. Each zone of the plurality of zones may be associated with a memory array region within a die or memory plane. Prior to performing a read or verify operation on a group of memory cells, a bit line read voltage used during sensing of the group of memory cells may be determined based on the plurality of bit line read voltages and a zone associated with the group of memory cells.
    Type: Application
    Filed: January 31, 2013
    Publication date: May 15, 2014
    Applicant: SANDISK TECHNOLOGIES, INC.
    Inventors: Teruhiko Kamei, Seungpil Lee, Siu Lung Chan, Kwang Ho Kim, Man Lung Mui
  • Publication number: 20140016415
    Abstract: A non-volatile storage system that performs a multi-stage programming process to program non-volatile storage to a set of data threshold voltage distributions. The multi-stage programming process includes performing a first stage of the multi-stage programming process to change threshold voltages of at least a subset of the non-volatile storage elements from an erased distribution to one or more intermediate distributions, performing an intermediate stage of the multi-stage programming process to change threshold voltages of at least some of the non-volatile storage elements to appropriate distributions of the data threshold voltage distributions, and performing a later stage of the multi-stage programming process, after performing the intermediate stage of the multi-stage programming process, to tighten only a subset of the data threshold voltage distributions.
    Type: Application
    Filed: July 11, 2012
    Publication date: January 16, 2014
    Inventors: Teruhiko Kamei, Cuong Trinh, Atsushi Inoue, Toshiyuki Takahashi
  • Patent number: 8400836
    Abstract: A set non-volatile storage elements are subjected to a programming process in order to store a set of data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target condition to store the appropriate data. Decisions about whether to continue programming or whether the programming is successful are made based on whether overlapping groups of the non-volatile storage elements have less than a threshold number of non-volatile storage elements that are not properly programmed.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: March 19, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Yan Li, Teruhiko Kamei, Jeffrey W. Lutze
  • Patent number: 7974124
    Abstract: Selecting circuits for columns of an array of memory cells are used to hold read data or write data of the memory cells. In a first set of embodiments, a shift register chain, having a stage for columns of the array, has the columns arranged in a loop. For example, every other column or column group could be assessed as the pointer moves in first direction across the array, with the other half of the columns being accessed as the pointer moves back in the other direction. Another set of embodiments divides the columns into two groups and uses a pair of interleaved pointers, one for each set of columns, clocked at half speed. To control the access of the two sets, each of which is connected to a corresponding intermediate data bus. The intermediate data buses are then attached to a combined data bus, clocked at full speed.
    Type: Grant
    Filed: June 24, 2009
    Date of Patent: July 5, 2011
    Assignee: SanDisk Corporation
    Inventors: Hardwell Chibvongodze, Manabu Sakai, Teruhiko Kamei
  • Publication number: 20110141819
    Abstract: A set non-volatile storage elements are subjected to a programming process in order to store a set of data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target condition to store the appropriate data. Decisions about whether to continue programming or whether the programming is successful are made based on whether overlapping groups of the non-volatile storage elements have less than a threshold number of non-volatile storage elements that are not properly programmed.
    Type: Application
    Filed: February 25, 2011
    Publication date: June 16, 2011
    Inventors: Yan Li, Teruhiko Kamei, Jeffrey W. Lutze
  • Patent number: 7924625
    Abstract: A set non-volatile storage elements are subjected to a programming process in order to store a set of data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target condition to store the appropriate data. Decisions about whether to continue programming or whether the programming is successful are made based on whether overlapping groups of the non-volatile storage elements have less than a threshold number of non-volatile storage elements that are not properly programmed.
    Type: Grant
    Filed: April 7, 2010
    Date of Patent: April 12, 2011
    Assignee: SanDisk Corporation
    Inventors: Yan Li, Teruhiko Kamei, Jeffrey W. Lutze
  • Publication number: 20100329007
    Abstract: Selecting circuits for columns of an array of memory cells are used to hold read data or write data of the memory cells. In a first set of embodiments, a shift register chain, having a stage for columns of the array, has the columns arranged in a loop. For example, every other column or column group could be assessed as the pointer moves in first direction across the array, with the other half of the columns being accessed as the pointer moves back in the other direction. Another set of embodiments divides the columns into two groups and uses a pair of interleaved pointers, one for each set of columns, clocked at half speed. to control the access of the two sets, each of which is connected to a corresponding intermediate data bus. The intermediate data buses are then attached to a combined data bus, clocked at full speed.
    Type: Application
    Filed: June 24, 2009
    Publication date: December 30, 2010
    Inventors: Hardwell Chibvongodze, Manabu Sakai, Teruhiko Kamei
  • Publication number: 20100195405
    Abstract: A set non-volatile storage elements are subjected to a programming process in order to store a set of data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target condition to store the appropriate data. Decisions about whether to continue programming or whether the programming is successful are made based on whether overlapping groups of the non-volatile storage elements have less than a threshold number of non-volatile storage elements that are not properly programmed.
    Type: Application
    Filed: April 7, 2010
    Publication date: August 5, 2010
    Inventors: Yan Li, Teruhiko Kamei, Jeffrey W. Lutze
  • Patent number: 7768834
    Abstract: A trial programming process is performed for a first set of one or more non-volatile storage elements to test usage of the non-volatile storage system. Based on this trial programming, a programming signal is calibrated by adjusting its initial magnitude. The calibrated programming signal is then used to program a second set of non-volatile storage elements (which may or may not include the first set).
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: August 3, 2010
    Assignee: SanDisk Corporation
    Inventors: Teruhiko Kamei, Yan Li