摘要 |
A method of erasing a sector for a flash memory device, the sector having a plurality of word lines with each word line having a plurality of memory cells therealong, each cell having a source region, comprises various steps. First, all of the memory cells in the sector are programmed. The memory cells are then simultaneously erased by applying a first voltage to the sources and a second voltage to the word lines. Subsequently, a first cell along a first word line is read to determine if the first cell is under-erased. Responsive to the first cell being under-erased, the first voltage is applied to the source region of the first cell and the second voltage is applied to the first word line while a third voltage is applied to the plurality of word lines except the first word line, the third voltage being higher than the second voltage.
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