Patent ID: 11894074
Assignee: KIOXIA CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 17:
18. The device of claim 1, wherein
the states include an eighth state, and a memory cell transistor whose threshold voltage is included in the eighth state stores eighth data,
where the eighth state is a state in which a program operation and a verify operation of a one-state preceding state are not executed in a write operation, the controller is configured to perform a verify operation of the eighth data such that:
a determination is made as to whether or not a threshold voltage of a memory cell transistor to which the eighth data is to be written exceeds a verify low voltage of the eighth data, while the verify low voltage of the eighth data is being applied to the word line; and
a determination is made as to whether or not a threshold voltage of the memory cell transistor to which the eighth data is to be written exceeds a verify high voltage of the eighth data, while the verify high voltage of the eighth data is being applied to the word line.