| 摘要 |
PURPOSE:To enlarge the voltage difference between the bits [1] and [0] at the time of reading and obtain high sensitivity, by providing a structure capable of varying equivalently the value of capacity of a condenser at the time of reading and that at the time of reading. CONSTITUTION:On the surface of P-type Si base 1 immediately below No.1 and No. 2 insulating 52 and 51, and on the surface of P-type Si base 1, other than the part on which N<+> layer 2 (the source region of the transistor) is formed, which is adjacent to the surface immediately below No. 2 insulating film 51, is formed No. 3 insulating film, consisting of a thin oxide film which makes it possible to form reverse layer 73 on the surface of P-type Si base 1 immediately below. Further, on No. 3 insulating film is formed No. 3 conducting film, consisting of poly-Si. Namely, in this structure, No. 3 conducting film and reverse layer 73, via No. 3 insulating film consisting of a thin oxide film, forms another condenser. Conducting film 62 of word line W is extended and connected to this No. 3 conducting film. |
