Patent ID: 11972797
Assignee: KIOXIA CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 14:
15. A method of performing a write operation in a memory device including a memory cell array having a plurality of memory strings, a plurality of first voltage applying electrodes, and a second voltage applying electrode, wherein each of the memory strings includes a select transistor and a plurality of memory cells connected in series, and each of the memory cells includes a cell transistor and a variable resistance layer connected in parallel, the cell transistor of each memory cell having a gate connected to one of the first voltage applying electrodes and the select transistor having a gate connected to the second voltage applying electrode, said method comprising:
at a first point in time, applying a first voltage to the first voltage applying electrodes, which include a selected first voltage applying electrode that is connected to the gate of a memory cell that is a write target, and non-selected first voltage applying electrodes that are respectively connected to the gates of other memory cells in the memory string of the write-target memory cell;
at a second point in time after the first point time, maintaining the voltage applied to the selected first voltage applying electrode at the first voltage and applying a second voltage higher than the first voltage to the non-selected first voltage applying electrodes;
at a third point in time after the second point time, maintaining the voltage applied to the non-selected first voltage applying electrodes at the second voltage and applying a third voltage lower than the first voltage to the selected first voltage applying electrode;
at a fourth point in time after the third point time, maintaining the voltage applied to the non-selected first voltage applying electrodes at the second voltage and applying the first voltage to the selected first voltage applying electrode; and
at a fifth point in time after the fourth point time, maintaining the voltage applied to the selected first voltage applying electrode at the first voltage and applying the first voltage to the non-selected first voltage applying electrodes.