| 摘要 |
PURPOSE:To increase a charge storage capacity, and to prevent difficulty of inversion of stored information even if charge leakage occurs by providing a plurality of cylinders for forming first electrodes of capacitors concentrically. CONSTITUTION:A first electrode 20 of a capacitor is formed of a disc 23 and two cylinders 24a, 24b provided concentrically on the disc 23, and a dielectric 21 and a second electrode 22 are provided on the outer surface of the electrode 20. The outer diameter of the disc 23 is set to substantially the same size and shape as those of prior art. An inner cylinder 24a is set to slightly larger inner diameter than that of a contact hole 16 of an insulating film 13, and smaller diameter than that of a conventional cylinder 24. On the other hand, the outer cylinder 24b is provided near the outer peripheral edge of the cylinder 23, and set to slightly larger inner diameter than that of the conventional cylinder 24. That is, in a capacitor, since the two cylinders 24a, 24b are provided, charge storage capacity is larger than that of prior art. |
