| 摘要 |
PURPOSE:To endure against a high voltage without sacrificing the integration by forming a field impurity region of high density directly under a selective gate between the drains of selecting transistors (Tr) of a pair of adjacent memory cells. CONSTITUTION:In an electric data erasable read-only semiconductor memory, a field implanted region 41 of high density of the same conductive type as a substrate is formed at the prescribed distance from a drain 15 on the substrate directly under a selective gate 16 made of a polycrystalline silicon layer. Further, a field implanted region of low density is formed on the substrate outside of the drain 15. Regions 18, 19, 20 of thin insulating films are formed between a common region 13 made of the source, of selecting MOSTr and the drain of data storing MOSTr and a floating gate 12 of the data storing MOSTr in this memory cell. |
