| 摘要 |
<p>PURPOSE:To obtain a nonvolatile memory, which decreaces its area to lower a write resistance and is never reduced a breakdown strength, by a method wherein an auxiliary transistor is used only at the time of writing and an increase in current is contrived. CONSTITUTION:When a bit line 7a is selected, an insulating film 8a for fuse use is broken, a current flows to a select transistor 10a and at the same time, the current flows also to a select transistor 10b through an auxiliary transistor 9a. In order to prevent an insulating film 8b for fuse use from being broken, the ON resistance ratio of the transistor 10a to the transistor 9a is adjusted in such a way that a potential difference between the drain side potential of the transistor 10b and the potential of a bit line 7b is smaller than the dielectric breakdown strength of the film 8b. Moreover, the threshold value of the transistor 9a is adjusted in such a way that the transistor 9a is turned-OFF at the time of readout of a memory cell and a nonvolatile memory, which can reduce write and readout resistances without enlarging the size of the memory cell and is never reduced a breakdown strength, can be realized.</p> |
