Nonvolatile memory device and method of operating the same

摘要

According to example embodiments, an operation method of a nonvolatile memory device includes determining a location of a selected word line among word lines connected to the nonvolatile memory device, selecting one of a plurality of different read disturbance reducing modes according to the location of the selected word line, and performing a read or verification operation according to the selected read disturbance reducing modes. The nonvolatile memory device includes cell strings. Each one of the cell strings includes memory cells stacked on top of each other in a direction perpendicular to the substrate and between a ground select transistor and a string select transistor. The ground select transistor is between the substrate and the number of the memory cells. The string select transistor is connected to a bit line and is between the bit line and the number of the memory cells.

主权项

1. A read method of a nonvolatile memory device which includes a plurality of cell strings, each of the cell strings including a plurality of memory cells connected in series, the plurality of memory cells being connected to a plurality of word lines, respectively and stacked in a direction perpendicular to a substrate, and each of the cell strings including a string select transistor connected to a string select line adjacent to a bit line and a ground select transistor connected to a ground select line adjacent to a source line, the read method comprising:
applying a first voltage to a first word line of the plurality of word lines and applying an unselected read voltage to an unselected word line during a pre-pulse section of a first read operation when the first word line is selected in the first read operation; and applying a second voltage to a second word line of the plurality of word lines and applying the unselected read voltage to an unselected word line during a pre-pulse section of a second read operation when the second word line is selected in the second read operation, wherein the first voltage is sufficiently high to turn on memory cells connected to the first word line and the second voltage is less than the first voltage.