| 摘要 |
PURPOSE:To increase a capacity without increasing an area by forming a capaci tor in a fine groove formed on a substrate, and forming a MOS for a switch thereon. CONSTITUTION:After an element separating oxide film 12 is formed on an Si substrate 11, a fine groove is formed on the substrate 11, and an insulating film 14 is formed by oxidizing on the inner surface of the groove. Then, a first electrode 15 is formed of polysilicon, and a dielectric film 16 is formed by oxidizing thereon. Thereafter, a polysilicon which becomes a second electrode 17 is deposited, and the electrodes 17 are separated at each memory cell. Then, the groove is buried with a second insulating film 18 to flatten the surface. In addition, a single crystal semiconductor layer 19 connected to the electrode 17 is formed thereon. A gate insulating film 20, a gate electrode 21 are formed on the layer 19, a source region 22 to be connected to the electrode 17, and a drain region 23 to be connected to a bit line 25 are formed. Since the capaci tor of the cell is formed in the groove, increases in the capacity and the density can be simultaneously performed. Since the capacitor is completely separated from the substrate, it is not affected by the influence of charge generated in the substrate due to alpha-rays. |
