| 摘要 |
PURPOSE:To obtain the capacitor large in an electrostatic capacity with a smaller area by expanding the area of opposed electrodes with a three-dimensional construction of the electrostatic capacity section formed on a semiconductor substrate. CONSTITUTION:When the first polycrystalline Si body 4' composing one of electrostatic capacity sections is formed on the semiconductor substrate 1, a dielectric insulator film 3 is applied over the entire substrate 1 and a contact region R of a small area is opened in the center thereof to have the Si body 4' contacting the substrate 1. Then, an Si body 4' having a pillar-shaped part in the center of the undersurface thereof while a top of a large area parallel to the substrate 1 is formed with the undersurface of the pillar-shaped part contacting the region R and the surface of the Si body 4' is covered with a dielectric insulator film 3' being integrated with the film 3. Thereafter, the circumference of the Si body 4' is entirely wrapped with the second Si body 5 serving as an electrostatic capacity section by way of the films 3 and 3' and the assembly is enclosed by a thick insulator film 3. This allows the Si body 4' to serve as an electrostatic capacity section both in the surface and back thereof, thereby enhancing the capacity in proportion to increment in the area. |
