Memory device and data erasing method thereof

Abstract

A memory device and a data erasing method are provided. The data erasing method includes: performing a first data erasing operation on a memory block, wherein the memory block includes a first word line to an Nth word line, and N is a positive integer greater than 1; performing an erase verification operation on the first word line to the Nth word line of the memory block one by one sequentially; finding a failed word line of a memory cell where a first verification failure occurs in the erase verification operation; and making the failed word line to the Nth word line at least one selected word line, making remaining word lines at least one non-selected word line, masking the at least one non-selected word line, and performing a second data erasing operation on a memory cell of the at least one selected word line.

Dependencies are inferred from the claim text.