| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the drain disturb effect of a flash memory. SOLUTION: A semiconductor device has a whole read bit line 12, a whole write bit line 14 and local bit lines 15 for a flash memory cell array and each column of cells, the column of the cells is divided into sub-columns, and the individual local bit lines are electrically connected to the cells of associated sub-columns. The local bit lines are coupled and decoupled with the whole read bit line through local read selection transistors 18 and coupled and decoupled with the whole write bit line through local write selection transistors 20. One local bit line for the column is coupled with the whole read bit line and other local bit lines are coupled with the whole write bit line. Thus, if a cell to be read and a cell to be written exists on the same column, a data is written in one cell and a data is read from the other cell.</p> |
