METHOD FOR MANUFACTURING DECOUPLING CAPACITOR OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating a decoupling capacitor of a semiconductor device is provided to improve the reliance and features of the semiconductor device by forming the decoupling capacitor to have an increased capacitance. CONSTITUTION: An isolation area and a decoupling capacitor forming area(200) are formed on a semiconductor substrate(31) by patterning a pad oxidized film(33) and a pad nitride film(35). A nitride film spacer is formed on a side wall of the structure consisting of the pad oxidized film(33) and the pad nitride film(35). An isolation film(39) is formed on the isolation area. By etching the nitride film spacer and the pad nitride film(35), the semiconductor substrate(31) corresponding to the decoupling capacitor forming area is exposed. Then, a plurality of trenches(41) are formed on the semiconductor substrate(31) corresponding to the decoupling capacitor area. After forming a gate oxidized film(43) and a conductive layer(45), the gate oxidized film(43) and the conductive layer(45) are patterned so that a gate electrode and a decoupling capacitor are provided.