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公开(公告)号:US20240420774A1
公开(公告)日:2024-12-19
申请号:US18815433
申请日:2024-08-26
Applicant: KIOXIA CORPORATION
Inventor: Jun NAKAI , Noboru SHIBATA
Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory cell array and a control unit. The memory cell array includes a plurality of memory cells arranged in a matrix. The control unit erases data of the memory cells. The control unit interrupts the erase operation of the memory cells and holds an erase condition before the interrupt in accordance with a first command during the erase operation, and resumes the erase operation based on the held erase condition in accordance with a second command.
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公开(公告)号:US20240265984A1
公开(公告)日:2024-08-08
申请号:US18432269
申请日:2024-02-05
Applicant: Kioxia Corporation
Inventor: Noboru SHIBATA , Kikuko SUGIMAE , Yusuke ARAYASHIKI , Katsuya NISHIYAMA , Motohiko FUJIMATSU , Akiyuki MURAYAMA
CPC classification number: G11C16/3459 , G11C16/102 , G11C16/26
Abstract: According to one embodiment, a memory device includes a first memory cell and a sequencer. The first memory cell is configured to store multi-bit data with a k-value threshold voltage level (k is an integer of 2 or larger). The sequencer is configured to execute a write operation having a loop process including a program operation and a verify operation. The program operation includes a first program process and a second program process. The sequencer is further configured to cause the first memory cell to store data by either the first program process or the second program process according to data to be written into the first memory cell in the write operation.
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公开(公告)号:US20240047001A1
公开(公告)日:2024-02-08
申请号:US18486433
申请日:2023-10-13
Applicant: Kioxia Corporation
Inventor: Noboru SHIBATA
CPC classification number: G11C16/3445 , G11C16/14 , G11C16/10 , G11C16/26
Abstract: In a memory cell array, a plurality of memory cells connected to a plurality of word lines and a plurality of bit lines are arranged in a matrix. A control circuit controls the potentials of said plurality of word lines and said plurality of bit lines. In an erase operation, the control circuit erases an n number of memory cells (n is a natural number equal to or larger than 2) of said plurality of memory cells at the same time using a first erase voltage, carries out a verify operation using a first verify level, finds the number of cells k (k≤n) exceeding the first verify level, determines a second erase voltage according to the number k, and carries out an erase operation again using the second erase voltage.
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公开(公告)号:US20230245697A1
公开(公告)日:2023-08-03
申请号:US18131511
申请日:2023-04-06
Applicant: Kioxia Corporation
Inventor: Noboru SHIBATA
CPC classification number: G11C11/5635 , G11C11/5642 , G11C16/3459 , G11C16/10 , G11C11/5628 , G11C16/0483
Abstract: According to one embodiment, a semiconductor memory device includes a memory cell array, a data storage circuit and a control circuit. The data storage circuit holds first data to be written into the memory cell and holds 1 bit data calculated from the first data. The control circuit writes the data of n bits into the memory cell in a first write operation and then executes a second write operation. The control circuit carries out the following control in the second write operation. It reads data stored in the memory cell in the first write operation. It restores the first data based on the data read from the memory cell and the 1 bit data held in the data storage circuit. It writes the restored first data into the memory cell.
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公开(公告)号:US20230018514A1
公开(公告)日:2023-01-19
申请号:US17956648
申请日:2022-09-29
Applicant: Kioxia Corporation
Inventor: Noboru SHIBATA , Hiroshi SUKEGAWA
Abstract: A communication line is connected to first and second chips, and held at a first signal level. A monitor circuit changes a signal level of the communication line from the first signal to a second signal level while one of the first and second chips uses a current larger than a reference current. When the signal level of the communication line is the second signal level, the other of the first and second chips is controlled to a wait state that does not transfer to an operating state of using a current larger than the reference current.
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公开(公告)号:US20210264990A1
公开(公告)日:2021-08-26
申请号:US17244246
申请日:2021-04-29
Applicant: Kioxia Corporation
Inventor: Noboru SHIBATA , Hironori UCHIKAWA , Taira SHIBUYA
Abstract: A semiconductor memory includes a first memory cell configured to be set with a first threshold voltage, the first threshold voltage being one of different threshold voltage levels, a second memory cell configured to be set with a second threshold voltage, the second threshold voltage being one of different threshold voltage levels, a first word line coupled to the first memory cell, a second word line coupled to the second memory cell, and a controller configured to read data of one of different bits based on a combination of the first threshold voltage of the first memory cell and the second threshold voltage of the second memory cell.
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公开(公告)号:US20230282276A1
公开(公告)日:2023-09-07
申请号:US18196263
申请日:2023-05-11
Applicant: Kioxia Corporation
Inventor: Noboru SHIBATA , Tokumasa HARA
CPC classification number: G11C11/5628 , G11C11/5642 , G11C16/08 , G11C16/26 , G11C16/10 , G11C16/32 , G11C16/3459 , G06F13/16 , G11C16/0483 , G11C2211/5648
Abstract: A semiconductor memory device includes a first memory cell for storing data using at least three levels of threshold voltages, including a first level, a second level higher than the first level and a third level higher than the second level. A first word line is connected to the first memory cell. In writing of data to the first memory cell from a state where a threshold voltage of the first memory cell is the first level, a plurality of program operations and verify operations are performed, each program operation including applying a program voltage to the first word line, each verify operation including applying a read voltage lower than the program voltage. The program operations include a program operation for the second level and a program operation for the third level, and the verify operations include a verify operation for the second level, and do not include a verify operation for the third level.
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公开(公告)号:US20230238059A1
公开(公告)日:2023-07-27
申请号:US18295504
申请日:2023-04-04
Applicant: KIOXIA CORPORATION
Inventor: Tokumasa HARA , Noboru SHIBATA
CPC classification number: G11C11/5628 , G11C16/0483 , G11C16/14 , G06F3/0679 , G06F11/1068 , G06F3/0619 , G06F3/0659 , G11C16/10
Abstract: A memory system includes a nonvolatile memory which comprises a plurality of memory cells capable of storing 4-bit data represented by first to fourth bits by sixteen threshold regions, and a memory controller configured to cause the nonvolatile memory to execute a first program for writing data of the first bit, the second bit, and the fourth bit and then causes the nonvolatile memory to execute a second program for writing data of the third bit. In fifteen boundaries existing between adjacent threshold regions among the first to sixteenth threshold regions, a maximum value of the number of first boundaries used for determining a value of the data of the first bit, the number of second boundaries used for determining a value of the data of the second bit, the number of third boundaries used for determining a value of the data of the third bit.
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公开(公告)号:US20220157387A1
公开(公告)日:2022-05-19
申请号:US17471810
申请日:2021-09-10
Applicant: Kioxia Corporation
Inventor: Tokumasa HARA , Noboru SHIBATA
Abstract: According to one embodiment, a semiconductor memory includes: a memory group including a plurality of memory cells configured to store a plurality of bits of data in three or more plurality of states; a word line coupled to the plurality of memory cells; and a first circuit configured to convert one external address received from an external controller into a plurality of internal addresses, wherein a first page size of page data of the memory group is smaller than a second page
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公开(公告)号:US20220148651A1
公开(公告)日:2022-05-12
申请号:US17582330
申请日:2022-01-24
Applicant: Kioxia Corporation
Inventor: Tokumasa HARA , Noboru SHIBATA
Abstract: A memory system has a nonvolatile memory which comprises memory cells capable of storing 4-bit data of first to fourth bits by sixteen threshold regions including a first threshold region corresponding to an erased state and second to sixteenth threshold regions having higher voltage levels than a voltage level of the first threshold region corresponding to a written state; and a controller which causes the nonvolatile memory to execute a first program for writing data of the first bit and the second bit and then causes the nonvolatile memory to execute a second program for writing data of the third bit and the fourth bit. The controller controls such that the threshold region is any threshold region of a seventeenth threshold region corresponding to an erased state and eighteenth to twentieth threshold regions having higher voltage levels than that of the seventeenth threshold region corresponding to a written state.
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