| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain a stable reference current, by suppressing variations in the threshold with time in a reference cell in an electrically rewritable flash memory for integrating MONOS-type transistors. <P>SOLUTION: With a semiconductor substrate 1 as ground potential, a positive voltage Vp is applied to a gate 4, a source 3, and a drain 2 of the reference cell. Accordingly, writing operation is performed for injecting hot electrons, accelerated by an electric field applied to a depletion layer, directly below the channel 9, to a silicon nitride layer 6 on the channel 9, and hence, a fixed load charge 8 is distributed uniformly to the entire region in the silicon nitride film 6 on the channel 9. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
