| 摘要 |
PROBLEM TO BE SOLVED: To improve program disturbance due to fineness, in a multi-level flash memory of an AND type in which QPW operation can be performed.SOLUTION: For example, at QPW operation, a corresponding bit line BL is biased, until a threshold value of a selection memory cell MC reaches to a verify-low-level by a plurality of sense amplifiers 201 provided corresponding to a plurality of bit lines BL; the corresponding bit line BL is biased to higher voltage than voltage VSS, when the threshold of the selection memory cell MC reaches a verify-low-level, when the threshold of the selection memory cell MC reaches to the verify-low-level; the corresponding bit line BL is continued to bias to further higher voltage VDDSA than voltage Vb; and bit lines BL corresponding to non-selection memory cells other than the selection memory cell Mc are continued to bias to voltage VDDSA. |
