METHOD FOR FORMING CAPACITOR OF SEMICONDUCTOR DEVICE TO IMPROVE RELIABILITY OF CAPACITOR

摘要

PURPOSE: A method for forming a capacitor of a semiconductor device is provided to improve reliability of a capacitor by preventing dopants from being depleted in doped polysilicon as an upper electrode material. CONSTITUTION: A lower electrode(2) is formed on a semiconductor substrate(1) having a predetermined underlying structure. An ONO(oxide nitride oxide) layer and a doped polysilicon layer are formed as materials for a dielectric layer(3a) and an upper electrode(4a) on the substrate to cover the lower electrode. Phosphorous ions(5) are implanted into an intermediate depth of the doped polysilicon layer. The doped polysilicon layer doped with phosphorous ions and the ONO layer are patterned to form an upper electrode and a dielectric layer.