CELL CAPACITOR STRUCTURE OF SEMICONDUCTOR DEVICE AND FABRICATION METHOD THEREOF

摘要

PURPOSE: A cell capacitor structure of a semiconductor device and fabrication method thereof is to increase the surface area of storage polycrystalline silicon layer, thereby enhancing the static capacitance of capacitor. CONSTITUTION: A cell capacitor structure of a semiconductor device comprises a semiconductor substrate(10), a storage polysilicon layer(23) formed on the semiconductor substrate and having a plurality of fine grooves(24) at the surface thereof, a dielectric layer(15) formed on the storage polysilicon layer and a plate polysilicon layer(17) formed on the dielectric layer. A fabrication method of a cell capacitor structure comprises the steps of: depositing the storage polysilicon film on the semiconductor substrate; forming the plurality of fine groove by in-situ etching the storage polysilicon film using an ammonium etchant.