NONVOLATILE MEMORY DEVICE, SYSTEM AND PROGRAMMING METHOD WITH DYNAMIC VERIFICATION MODE SELECTION

摘要

Nonvolatile memory devices, memory systems and related methods of operating nonvolatile memory devices are presented. During a programming operation, the nonvolatile memory device is capable of using bit line forcing, and is also capable of selecting a verification mode for use during a verification operation from a group of verification modes on the basis of an evaluated programming condition.

主权项

1. A method of operating a nonvolatile memory device including a plurality of multi-level memory cells, the method comprising:
applying a first programming voltage to a selected wordline; after the first programming voltage is applied to the selected wordline, performing a first two-step operation on memory cells connected to the selected wordline, the first two-step operation including performing a first pre-verification operation on the memory cells using a first threshold voltage and performing a first verification operation on the memory cells using a second threshold voltage greater than the first threshold voltage; after the first programming voltage is applied to the selected wordline, performing a second two-step operation on the memory cells, the second two-step operation including performing a second pre-verification operation on the memory cells using a third threshold voltage greater than the second threshold voltage and performing a second verification operation on the memory cells using a fourth threshold voltage greater than the third threshold voltage; applying a second programming voltage to the selected wordline, the second programming voltage being greater than the first programming voltage; and after the second programming voltage is applied to the selected wordline, performing a third one-step operation on the memory cells, the third one-step operation consisting essentially of performing a third verification operation on the memory cells using a fifth threshold voltage greater than the fourth threshold voltage.