| 摘要 |
PURPOSE:To provide a semiconductor memory device having a broad operating, margin, by the constitution wherein the thickness of an insulating film of a capacitor in a memory element is different from the thickness of an insulating film of a capacitor in a reference memory element. CONSTITUTION:The capacity per unit area of a capacitor in a reference memory element is 1/2 that in a memory element. The capacitor 10 in the memory element and the capacitor 11 in the reference memory element can be made to have the same area and also the same configuration. The control of the thickness of an insulating film is easy in comparison with the control of the pattern width in a photoetching process. Therefore, the deviation from the preset value of the ratio of CS and CR can be made minimum. In a 1-Tr type dynamic RAM, a double layered polycrystal semiconductor is widely used. Therefore, the processes do not become longer in comparison with conventional methods. |
