| 摘要 |
PURPOSE:To obtain a semiconductor memory device having a large capacity and little indentation of the surface of a substrate by a method wherein a conductor having the same potential as a semiconductor substrate is formed on a gate electrode of a capacitor element with an oxide film interposed between them. CONSTITUTION:A capacitor element is so designed as to have a semiconductor substrate 11 of a first conductivity type, a groove 16 provided in the surface of this substrate 11, a semiconductor layer 17 provided inside the groove 16 and around it, a gate electrode 19 provided on this semiconductor layer 17 with a gate oxide film 18 interposed between them, and a conductor 22 which is provided on the gate electrode 19 with an oxide film 20 interposed between them and has the same potential as the substrate 11. For instance, an N<-> layer 17 is formed inside and around the groove 16 formed in the Si substrate 11 of a P-type, a polycrystalline Si layer is formed thereon with the gate oxide film 18 interposed between them, and the gate electrode 19 is formed with resistance reduced. After a second-layer polycrystalline Si layer is deposited through the oxide film 20, subsequently, resistance is reduced and a potential take-out region 21 of an N<+> type formed. Then, the second-layer polycrystalline Si layer is removed selectively, so as to form the conductor 22 having the same potential as the substrate 11. |
