PURPOSE: To enable the erasure and rewriting of stored content in a non-volatile memory by forming the second electrode further on a silicon oxidized film.
CONSTITUTION: Drain and source regions 25, 26 are fomed at the perdetermined interval in a semiconductor substrate 24, and a gate insulating film 22, the first gate electrode 28, an insulating film (silicon oxidized film) 27 and the second gate electrode 23 are laminated between the regions 25 and 26 on the substrate 24. Then, a pinch-off region 31 is formed on the substrate 24, and to set the potential of the regin 31 to a voltage adapted to reach the first gate electrode 28, the impurity density of the region 31 and the vicinity are increased from that of the other part. Thus, the writing and rewriting of information can be effectively performed as required mereby by altering the bias condition, and information once written can be retained without application of bias.
TARUI YASUO
NAGAI KIYOKO
| JPS5537107A | 1980-03-15 |