| 摘要 |
PURPOSE:To highly integrate a dynamic memory device by forming the impurity density of a channel stopper in a low density in a memory cell region and in a high density in the region except the memory cell region in an MOS dynamic memory device, thereby reducing the capacity of a bit line. CONSTITUTION:A reverse conductive type impurity diffused layer 2 to become a bit line, a polycrystalline Si layer 5, an insulating film 7 and a polycrystalline Si layer 6 are formed on a semiconductor substrate 1. Thus, an inversion layer 3 is produced, and an MOS transistor to become a memory cell with the layer 3, the layer 6 of the second layer and the layer 2 is formed. 4, 4' are channel stoppers, which are low in the impurity density in the memory cell region, and high in a peripheral circuit region 4'. The difference of the density is preferably approx. 20%. In this manner, a capacity formed of the bit line 2 and the stoppers becomes small, thereby preventing the attenuaion of a signal voltage read out on the bit line. |
