| 摘要 |
PROBLEM TO BE SOLVED: To secure larger capacity without increasing the area of a semiconductor memory cell by positioning the interface between the first conductor film and a dielectric film higher than a gate electrode and an insulating film covering the gate electrode. SOLUTION: A part of the first interlayer insulating film 6 on an n-type source/drain region 5a is removed, and polysilicon is stacked, and phosphor is diffused thermally to form the first conductor film 7. Subsequently, a silicon nitride film of a specified thickness is stacked to form an insulating film. Then, other is etched off, leaving only the first conductor film 7 right under the insulating film. After that, polycrystalline silicon is stacked and phosphor is diffused thermally to get the second conductor film 8. Next, a capacitive insulating film 9 being the dielectric consisting of a silicon oxide film is made, and then the stacking, the thermal diffusion, and the patterning of the polycrystalline silicon film are performed to form a cell plate 10. Then, the interface between the first dielectric film 7 and the dielectric is positioned higher than a gate electrode 4 and the insulating film covering the gate electrode 4. |
