| 摘要 |
PURPOSE:To obtain a fine dynamic memory cell where a MOS transistor is completely separated from a capacitor for memory use with a view to being in compliance with the high integration by forming a first single-crystal silicon layer which is formed on a first insulating layer formed on one main surface of a silicon single-crystal substrate and by forming a second single-crystal silicon layer which is formed along the wall surface of a second insulating layer and along the wall surface of a low-resistance part, both wall surfaces being formed on the first single-crystal silicon layer. CONSTITUTION:At a p-type silicons substrate 21 whose main plane has a crystal orientation of 100 and which is doped with boron ions, a silicon nitride film is formed on an oxide film 41 as a base layer; a pattern 42 remains unremoved. When an SiO2 layer 22 is formed, a polycrystalline silicon layer 43 is deposited, and an argon laser beam 44 is illuminated, the polycrystalline silicon layer 43 is melted and then recrystallized, and is transformed into a single-crystal silicon layer 23. An opening with a depth of about 8 mum is made in such a way that is can reach the silicon substrate 21; an SiO2 layer 49 is formed on a side wall 26 at the opening of the silicon substrate and on a wall surface of the single-crystal silicon layer 23. If an n-type polycrystalline silicon layer is deposited to be thick and is etched back from the surface, a structure filled with a polycrystalline silicon material 27 only at the inside of the opening can be formed. If the SiO2 layer 49 at the wall surface is removed, a diffused layer 24 of single-crystal silicon is exposed. |
