| 摘要 |
PURPOSE: An erase operating method of a flash memory is provided to prevent the increase of threshold voltage distribution by dividing a plurality of post program operations after erasure operation. CONSTITUTION: An erase operation is executed for selected all memory cells(301). A first post program operation and a first post program verification operation are executed in order to increase the threshold voltage distribution of memory cells in which the erase operation is completed(303). The channel voltage of the string passing the first post program verification action is increased(306). A second post program operation and a second post program verification operation are executed for all memory cells(308). |
