| 摘要 |
PURPOSE:To enhance the dielectric strength between electrodes by a method wherein about the half of the growth film thickness of polysilicon for charge storage use is isotropically etched by a wet etching operation and the residual polysilicon is anisotropically etched by a dry etching operation. CONSTITUTION:Polysilicon 7, for charge storage use, which forms a lower-part electrode for a capacity part is grown; phosphorus is diffused; and after that, a photoresist 9 is patterned. Then, about the half of the growth film thickness of the polysilicon 7 for charge storage use is isotropically etched by a wet etching operation. Then, a residual part 16 is anisotropically etched by a dry etching operation; charge-storage upper-part electrodes 17-A, 17-B by means of the polysilicon are formed; and the photoresist 8 is removed. Then, a capacity insulating film 10 is grown; capacity polysilicon 13 to be used as an upper-part electrode for the capacity part is grown on it. Thereby, the dielectric strength between the polysilicon 7 for charge storage use in the lower-part electrode and the capacity polysilicon 13 in the upper-part electrode is enhanced. |
