| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem that it is difficult to increase writing speed because a distribution width of threshold voltage of each data needs to be narrowed. <P>SOLUTION: A semiconductor memory includes: a semiconductor substrate; a memory cell array that is coupled to word lines and bit lines and in which a plurality of serially connected memory cells is placed in a matrix; a selection transistor for selecting the word lines; and a control circuit for controlling potential of the word lines and bit lines according to input data and controlling write, read and delete operations of data for the memory cells. The selection transistor is formed on a well of the semiconductor substrate. At the time of the write operation, a second negative voltage is input to the well and a third voltage (the third voltage≥the second negative voltage) is input to a predetermined unselected word line. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
