| 摘要 |
PURPOSE:To prevent the formation of a channel on the side surface of a transistor, by arranging a first electrode and a second electrode in a trench to form a capacitance, via an insulating film. CONSTITUTION:On the outer peripheral part of a semiconductor substrate 1, a trench 19 is formed, in which a capacitor C is formed. On the side surfaces of transistors 9-12 formed in a memory cell region, a first electrode 5 is formed via an insulating film 4. A second electrode 7 connecting with the drain 12 of the transistors 9-12 is formed via a second insulating film 6, so as to cover the first electrode 5. Thereby it can be always prevented that a channel is formed on the side surfaces of transistors, even in the case where the electric potential of the second electrode 7 is higher than that of a common wiring part 14. Further, since the peripheral length of a capacitor can be made long, the capacitance can be made large, even if the area of memory cell is made small. |
