| 摘要 |
PURPOSE:To prevent the crystal grains of a poly-Si layer from growing big and to prevent the deterioration of a dielectric film, by a method wherein the poly-Si layer is connected to a single crystal Si layer through an amorphous film. CONSTITUTION:The impedance element of a memory cell of a DRAM is constituted of a lower electrode 12 consisting of a poly Si layer, a dielectric film 13 consisting of an Si oxide film and an upper electrode 14 consisting of a poly Si layer. The electrode 14 is given a constant potential (for example, an earth potential) and the electrode 12 is connected to a drain electrode (n<+> region) of a MOSFET formed on a p<-> single crystal Si substrate 1. At this time, an amorphous film 9 of about 30 Angstrom and consisting of a thin Si oxide film is provided between the region 8 and the electrode 12. Whereupon, the crystal grains of the electrode 12 can be free from growing big at the time of formation of the electrode 12 and the deterioration of the film 13 can be prevented. As the film 9 is thin, electrons flow between the region 8 and the electrode 12 by a tunnel phenomenon. |
