| 摘要 |
PURPOSE:To improve the cell breakdown strength and holding characteristics of various memory cells, and to attain ultrahigh integration by forming trenches, penetrating a second insulating film unified with a first insulating film burying a section between insular single crystal silicon layers and the single crystal silicon layers and shaping a capacitor with a lower electrode brought into contact with the single crystal silicon layers, a dielectric film and an upper electrode. CONSTITUTION:An silicon substrate 11, a first insulating film such as a porous silicon oxide film 2a shaped onto the silicon substrate, insular single crystal silicon layers 13 on the insulating film 2a, a second insulating film such as a porous silicon oxide film 2b burying a section between the insular silicon layers 13 and being unified with the first insulating film, and trenches 3, which are extended up to the inside of the first insulating film 2a, penetrating the silicon layer 13 and one side surfaces of which coincide with the side surfaces of the second insulating film 2b, are shaped. Lower electrodes 51 consisting of polysilicon are formed onto the side surfaces and bases of the trenches 3, dielectric films 4 are shaped onto the electrodes 5, and an upper electrodes 52 composed of polysilicon completely burying the trenches is formed onto the films 4. |
