Capacitor having high dielectric layer in semiconductor memory device and method for fabricating the same

PURPOSE: A capacitor of a semiconductor memory device using a ferroelectrics material as a dielectric film and a manufacturing method thereof are provided to use a polysilicon film as a lower and an upper electrode for the dielectric film consisting of the ferroelectrics material by forming an oxidation barrier film on the upper electrode and under the upper electrode. CONSTITUTION: A semiconductor substrate(100) has an active area(120) defined by the device isolation film(110). An interlayer insulation film(200) is formed on the active area. A gate insulation film and a gate electrode are formed on the active area and the gate insulation film and the gate electrode are covered by the interlayer insulation film. The lower electrode(300) of the capacitor consisting of the polysilicon film is formed on the interlayer insulation film. The lower electrode is directly connected to the impurity area of the active area by penetrating the interlayer insulation film. The lower oxidation barrier film(350) is formed on the lower electrode. The dielectric film(400), the upper oxidation barrier film(550) and the upper electrode(500) are successively formed on the oxidation barrier film. 본 발명의 반도체 메모리 소자의 커패시터는, 반도체 기판의 액티브 영역과 전기적으로 연결된 폴리실리콘막 하부 전극과, 이 폴리실리콘막 하부 전극 위의 하부 산화 방지막과, 이 하부 산화 방지막 위의 고유전 물질로 이루어진 유전막과, 이 유전막 위의 상부 산화 방지막, 및 상부 산화 방지막 위의 폴리실리콘막 상부 전극을 구비한다.