| 摘要 |
PURPOSE:To prevent a breakdown strength from being deteriorated at a corner of a lower-part electrode of a storage capacitance part and to prevent a leak by a method wherein a cross-sectional shape on the surface of a first electrode used as the lower-part electrode of the storage capacity part connected electrically to a source region of an insulated gate field-effect transistor is formed to be rounded. CONSTITUTION:A silicon layer 9 connected electrically to a source diffusion layer 5 from a contact part is grown selectively in 400Angstrom ; it is spread on a CVD silicon oxide film 7; a lower-part electrode whose cross-sectional shape on the surface is rounded is formed. After that, e.g. P ions at 5.0X10<15>cm<-3> are implanted into the silicon layer 9 at 100keV; thereby, its electrical conductivity is made good. After that, e.g. a CVD silicon nitride film 10 is grown in 200Angstrom as an insulating film for capacitance use; after that, e.g. a polycrystalline silicon layer 11 is laminated in 3000Angstrom as a second conductive layer film; a part other than a part to be used as an upper-part electrode of a capacitance part is removed by, e.g. a reactive ion etching operation by making use of a photoresist 12 as a mask; a storage capacitance part is formed. |
