| 摘要 |
PURPOSE:To enlarge the effective area and to increase element density by a circuit wherein passive elements or active elements are formed on the rugged surface. CONSTITUTION:Thick field oxide films 2, 2 locally projected on both sides and thick field oxide films 3, 3... are formed on the surface of a semiconductor substrate 1 of one conductive type. Then, the intermediate thick oxide films 3, 3... are removed leaving the field oxide films 2, 2 on both sides to produce the rugged surface in the substrate, on which a diffusion layer 4 of conductive type opposite to that of the substrate is formed as a lower electrode. Subsequently, a capacity insulating film 5 is formed on the lower electrode 4 except for the leading port of an electrode terminal 4a. Then, an upper electrode 6 made of a polycrystal silicon or metal is formed on the insulating film 5, and both electrode terminals 4a and 6a are led out from the lower and upper electrodes, respectively. |
