| 摘要 |
PURPOSE:To increase the capacitance of a capacitor while reducing a plane area of the capacitor by forming the capacitor to the side surface of a groove formed to a predetermined section on a substrate and forming an insulating film for isolation to the bottom of the groove. CONSTITUTION:A pad silicon oxide film 203 on the bottom 82 of the groove is removed through etching, a silicon oxide film 41 is formed only onto the bottom 82 of the groove through selective oxidation in wet oxygen while using silicon nitride films 72, 74 as masks, and the silicon nitride films 72, 74 and pad silicon oxide films 202, 203 are removed through etching. As a result of a series of said processes, the groove 10 with the thick silicon oxide film 41 for isolation is formed onto the bottom. A silicon oxide film 21 is formed to the whole surface as an insulating film for the capacitor, and a substance such as phosphorus doped polycrystalline silicon 31 is deposited so as to completely fill the groove 103 as a conductor thin-film and patterned, thus forming the phosphorus doped polycrystalline silicon 31 only to a desired section. |
