| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a technique which suppresses a writing-prevention voltage drop so that incorrect writing to the unselected memory cell is prevented in a nonvolatile semiconductor memory device. <P>SOLUTION: The nonvolatile semiconductor memory device is a NAND-type flash memory which can be electrically written/erased. The nonvolatile semiconductor memory device includes at least three or more memory cell arrays (e.g., A page, B page, C page) in which a plurality of memory cells are connected in series and these memory cell arrays are adjacent to each other across an element isolation trench. A writing operation is performed individually to each of these memory cell arrays. In this manner, the writing-prevention voltage VH is surely applied to at least one side of both surfaces of the semiconductor substrate which are adjacent across the element isolation trench to the surface of the semiconductor substrate under the writing-prevented memory cell. Therefore, incorrect writing to an unselected memory cell can be largely reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
