| 摘要 |
PURPOSE:To improve the surface condition of an accumulation electrode so that the decline in capacity of the electrode can be prevented even when the film thickness of the electrode is reduced to about several nanometers by constituting the electrode of a polycrystalline semiconductor film, the grain size of which is larger than that of another semiconductor film which is originally formed as a polycrystalline film. CONSTITUTION:An accumulation electrode 27 is provided with one fin and a dielectric multilayered film 23 and a facing electrode (the second electrode) 24 are grown on the electrode 27. In addition, a stack type capacitor provided with the first electrode composed of a polycrystalline semiconductor film, the grain size of which is larger than that of another semiconductor film which is originally formed as a polycrystalline film, the dielectric film 23 formed on the surface of the first electrode, and the second electrode 24 covering the film 23 is formed. The first electrode has such a grain size that is obtained when an amorphous semiconductor layer is crystallized to a polycrystalline layer. When the stack type capacitor is formed in such a way, the capacitance of this semiconductor device does not drop even when the film thickness is reduced to about 3nm. |
