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).
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Patent number: 11735265Abstract: 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: GrantFiled: August 12, 2021Date of Patent: August 22, 2023Assignee: Kioxia CorporationInventor: Yukio Komatsu
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Publication number: 20220262440Abstract: 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: ApplicationFiled: August 12, 2021Publication date: August 18, 2022Applicant: Kioxia CorporationInventor: Yukio KOMATSU
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Patent number: 9754662Abstract: 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: GrantFiled: April 20, 2016Date of Patent: September 5, 2017Assignee: TOSHIBA MEMORY CORPORATIONInventor: Yukio Komatsu
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Publication number: 20160232967Abstract: 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: ApplicationFiled: April 20, 2016Publication date: August 11, 2016Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Yukio KOMATSU
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Patent number: 9349460Abstract: 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: GrantFiled: June 20, 2014Date of Patent: May 24, 2016Assignee: KABUSHIKI KAISHA TOSHIBAInventor: Yukio Komatsu
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Publication number: 20140301141Abstract: 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: ApplicationFiled: June 20, 2014Publication date: October 9, 2014Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Yukio KOMATSU
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Patent number: 8787093Abstract: 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: GrantFiled: February 6, 2013Date of Patent: July 22, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Yukio Komatsu
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Publication number: 20130286742Abstract: 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: ApplicationFiled: March 13, 2013Publication date: October 31, 2013Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Yuji KOMINE, Mitsuhiro KOGA, Yukio KOMATSU, Tomonari IWASAKI
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Patent number: 8391074Abstract: 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: GrantFiled: June 18, 2012Date of Patent: March 5, 2013Assignee: Kabushiki Kaisha ToshibaInventor: Yukio Komatsu
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Publication number: 20130015915Abstract: 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: ApplicationFiled: July 12, 2012Publication date: January 17, 2013Applicant: Kabushiki Kaisha ToshibaInventors: Yukio KOMATSU, Hitoshi Ohta, Daisuke Awano
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Publication number: 20120257456Abstract: 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: ApplicationFiled: June 18, 2012Publication date: October 11, 2012Inventor: Yukio KOMATSU
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Publication number: 20120254518Abstract: 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: ApplicationFiled: March 21, 2012Publication date: October 4, 2012Applicant: Kabushiki Kaisha ToshibaInventor: Yukio KOMATSU
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Patent number: 8223557Abstract: 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: GrantFiled: May 3, 2011Date of Patent: July 17, 2012Assignee: Kabushiki Kaisha ToshibaInventor: Yukio Komatsu
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Publication number: 20110205807Abstract: 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: ApplicationFiled: May 3, 2011Publication date: August 25, 2011Inventor: Yukio KOMATSU
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Patent number: 7948804Abstract: 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: GrantFiled: August 4, 2009Date of Patent: May 24, 2011Assignee: Kabushiki Kaisha ToshibaInventor: Yukio Komatsu
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Publication number: 20110063909Abstract: 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: ApplicationFiled: February 26, 2010Publication date: March 17, 2011Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Yukio KOMATSU
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Patent number: 7884000Abstract: 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: GrantFiled: April 3, 2007Date of Patent: February 8, 2011Assignee: Sumco CorporationInventors: Yoshiro Aoki, Riyuusuke Kasamatsu, Yukio Komatsu
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Patent number: 7807545Abstract: 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: GrantFiled: February 2, 2007Date of Patent: October 5, 2010Assignee: Sumco CorporationInventors: Yoshiro Aoki, Yukio Komatsu, Tetsuya Nakai, Seiichi Nakamura
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Publication number: 20100061148Abstract: 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: ApplicationFiled: August 4, 2009Publication date: March 11, 2010Inventor: Yukio KOMATSU
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Patent number: 7560363Abstract: 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: GrantFiled: July 19, 2005Date of Patent: July 14, 2009Assignee: Sumco CorporationInventors: Naoshi Adachi, Yukio Komatsu