| 摘要 |
PURPOSE:To obtain RAM whose capacitor has a large capacity by providing first the gate electrode of a transistor on the oxidized film of a semiconductor substrate and then forming a joined capacity through self-alignment just below the information accumulating capacitor by using the electrode as a mask. CONSTITUTION:When MOS dynamic RAM consisting of one transistor and one capacitor is prepared, first a gate oxidized film 2 and a field oxidized film 7 are formed on the surface of the p type semiconductor substrate 1. Next, the gate electrode 5 is provided in a prescribed region, a p<+> type region 9 is formed through injection of ion therein by using the electrode as the mask, an n<+> type region 8 is provided further in the region 9, the electrode 5 is covered with an oxidized film 10, and an accumulation gate electrode 3 is formed on the region 8. After that, the film 10 is formed into a prescribed pattern, a part of the electrode 5 exposed thereby is removed, and an n<+> type region 6 is formed diffusely, within the substrate 1 under the removed part. Thus, the capacity of the capacitor is increased without lowering integration of the device. |
