Patents by Inventor Yukio Komatsu

Yukio Komatsu 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: 11735265
    Abstract: According to a certain embodiment, the nonvolatile semiconductor memory device includes: a memory cell array including a plurality of selected blocks and a plurality of non-selected blocks; and a row decoder including a block decoder configured to switch between the selected block and the non-selected block. The row decoder switches a block determined to be a defective block to a non-selected block and switches a block determined not to be a defective block to a selected block, on the basis of the multi-level data. The block decoder includes a defective block flag circuit including a plurality of latch circuits configured to store multi-level data.
    Type: Grant
    Filed: August 12, 2021
    Date of Patent: August 22, 2023
    Assignee: Kioxia Corporation
    Inventor: Yukio Komatsu
  • Publication number: 20220262440
    Abstract: According to a certain embodiment, the nonvolatile semiconductor memory device includes: a memory cell array including a plurality of selected blocks and a plurality of non-selected blocks; and a row decoder including a block decoder configured to switch between the selected block and the non-selected block. The row decoder switches a block determined to be a defective block to a non-selected block and switches a block determined not to be a defective block to a selected block, on the basis of the multi-level data. The block decoder includes a defective block flag circuit including a plurality of latch circuits configured to store multi-level data.
    Type: Application
    Filed: August 12, 2021
    Publication date: August 18, 2022
    Applicant: Kioxia Corporation
    Inventor: Yukio KOMATSU
  • Patent number: 9754662
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Grant
    Filed: April 20, 2016
    Date of Patent: September 5, 2017
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventor: Yukio Komatsu
  • Publication number: 20160232967
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Application
    Filed: April 20, 2016
    Publication date: August 11, 2016
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yukio KOMATSU
  • Patent number: 9349460
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Grant
    Filed: June 20, 2014
    Date of Patent: May 24, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yukio Komatsu
  • Publication number: 20140301141
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Application
    Filed: June 20, 2014
    Publication date: October 9, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yukio KOMATSU
  • Patent number: 8787093
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: July 22, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yukio Komatsu
  • Publication number: 20130286742
    Abstract: According to one embodiment, a semiconductor memory device includes a memory cell array includes memory cells and a word line coupling the memory cells. A determination circuit determines whether write to a first memory cell group of the word line succeeded, and whether write to a second memory cell group of the word line succeeded. A test circuit counts application of write voltage during write to the word line, compares with a threshold a difference between a count of write voltage application upon success of one of respective writes to the first and second memory cell groups and a count of write voltage application upon success of the other of respective the writes, and outputs a result of the comparison.
    Type: Application
    Filed: March 13, 2013
    Publication date: October 31, 2013
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yuji KOMINE, Mitsuhiro KOGA, Yukio KOMATSU, Tomonari IWASAKI
  • Patent number: 8391074
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Grant
    Filed: June 18, 2012
    Date of Patent: March 5, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yukio Komatsu
  • Publication number: 20130015915
    Abstract: A semiconductor device including: a first pad to receive first and second test commands supplied from the outside; a voltage generator circuit to generate a test target voltage on the basis of the first and second test commands; a second pad to receive first and second monitor voltages supplied from the outside in response to respective of the first and second test commands, the first and second monitor voltages corresponding to respective lower and upper limit voltages of the test target voltage; and a comparator to output a first output signal at one of first and second logical levels by comparing the test target voltage with the first monitor voltage, and to output a second output signal at one of the first and second logical levels by comparing the test target voltage with the second monitor voltage.
    Type: Application
    Filed: July 12, 2012
    Publication date: January 17, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yukio KOMATSU, Hitoshi Ohta, Daisuke Awano
  • Publication number: 20120257456
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Application
    Filed: June 18, 2012
    Publication date: October 11, 2012
    Inventor: Yukio KOMATSU
  • Publication number: 20120254518
    Abstract: A memory system includes: a plurality of word lines; a plurality of bit lines; a plurality of memory cells each having a control gate and a drain end, the control gate being connected to one of the word lines, the drain end being connected to one of the bit lines; a memory cell array including a plurality of blocks, each of the blocks including a plurality of pages, each of the pages being including a plurality of the memory cells; and a storage area configured to hold good block data identifying whether or not each of the blocks is a good block based on the number of fail bits in each page in the good block being less than or equal to a first threshold, wherein the first threshold is smaller than a second threshold used for identifying whether or not each of the blocks is a bad block.
    Type: Application
    Filed: March 21, 2012
    Publication date: October 4, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventor: Yukio KOMATSU
  • Patent number: 8223557
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Grant
    Filed: May 3, 2011
    Date of Patent: July 17, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yukio Komatsu
  • Publication number: 20110205807
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Application
    Filed: May 3, 2011
    Publication date: August 25, 2011
    Inventor: Yukio KOMATSU
  • Patent number: 7948804
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Grant
    Filed: August 4, 2009
    Date of Patent: May 24, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yukio Komatsu
  • Publication number: 20110063909
    Abstract: A memory cell array and a peripheral circuit are provided. The memory cell array has a plurality of blocks which are erasing units respectively. Each of the blocks includes a plurality of memory cells. A block control unit operates according to input signals from outside and controls operation of the blocks. A ready/busy control circuit outputs a busy signal during a period of operation implementation for a block selected from the blocks, in response to an output from the block control unit. The ready/busy control circuit outputs a ready signal out of the period of the operation implementation for the selected block. A registration control unit registers the selected block as a bad block, in the case that the ready/busy control circuit outputs a busy signal when the registration control unit receives a bad block identification command.
    Type: Application
    Filed: February 26, 2010
    Publication date: March 17, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yukio KOMATSU
  • Patent number: 7884000
    Abstract: A method for manufacturing SIMOX wafer, wherein roughness (Rms) of an SOI layer and roughness (Rms) of an interface between the SOI layer and a BOX layer can be reduced. The method includes forming a first ion-implanted layer containing highly concentrated oxygen within a wafer; forming a second ion-implanted amorphous layer; and a high temperature heat treatment, transforming the first and second ion-implanted layers into a BOX layer by holding the wafer at a temperature between 1300° C. or more and a temperature less than a silicon melting point in an atmosphere containing oxygen, wherein when a first dose amount in forming the first ion-implanted layer is set to 2×1017 to 3×1017 atoms/cm2, the first implantation energy set to 165 to 240 keV and a second dose amount in forming the second ion-implanted layer is set to 1x1014 to 1x1016 atoms/cm2.
    Type: Grant
    Filed: April 3, 2007
    Date of Patent: February 8, 2011
    Assignee: Sumco Corporation
    Inventors: Yoshiro Aoki, Riyuusuke Kasamatsu, Yukio Komatsu
  • Patent number: 7807545
    Abstract: A SIMOX wafer having a BOX layer with a thin film thickness is obtained without a reduction in productivity or deterioration in quality. In a method for manufacturing a SIMOX wafer comprising: a step of forming a first ion-implanted layer in a silicon wafer; a step of forming a second ion-implanted layer that is in an amorphous state; and a high-temperature heat treatment step of maintaining the wafer in an oxygen contained atmosphere at a temperature that is not lower than 1300° C. but less than a silicon melting point for 6 to 36 hours to change the first and the second ion-implanted layers into a BOX layer, a gas containing chlorine that is not less than 0.1 volume % but less than 1.0 volume % is mixed into an atmosphere during temperature elevation in the high-temperature heat treatment.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: October 5, 2010
    Assignee: Sumco Corporation
    Inventors: Yoshiro Aoki, Yukio Komatsu, Tetsuya Nakai, Seiichi Nakamura
  • Publication number: 20100061148
    Abstract: A semiconductor memory device includes a control circuit. The control circuit executes control to perform a verify operation with respect to only a lowest threshold voltage level of a memory cell at a time of a data write operation, and to skip the verify operation with respect to the other threshold voltage levels. The control circuit determines whether a verify pass bit number of the lowest threshold voltage level, which is counted by a bit scan circuit, is a prescribed bit number or more, and the control circuit further executes control, if the verify pass bit number is the prescribed bit number or more, to perform the verify operation with respect to only the lowest threshold voltage level and a threshold voltage level that is higher than the lowest threshold voltage level, and to skip the verify operation with respect to the other threshold voltage levels.
    Type: Application
    Filed: August 4, 2009
    Publication date: March 11, 2010
    Inventor: Yukio KOMATSU
  • Patent number: 7560363
    Abstract: A manufacturing method for a SIMOX substrate for obtaining a SIMOX substrate by subjecting a silicon substrate having oxygen ions implanted thereinto by heat treatment at 1300 to 1350° C. in an atmosphere of a gas mixture of argon and oxygen, the method includes: performing a pre-heat-treatment to the silicon substrate for five minutes to four hours within the temperature range of 1000° C. to 1280° C. in an atmosphere of inert gas, reducing gas, or a gas mixture of inert gas and reducing gas, after the oxygen ions are implanted and before the heat treatment is performed.
    Type: Grant
    Filed: July 19, 2005
    Date of Patent: July 14, 2009
    Assignee: Sumco Corporation
    Inventors: Naoshi Adachi, Yukio Komatsu