METHOD FOR FABRICATING CAPACITOR HAVING TANTALUM OXIDE FILM AS DIELECTRIC FILM

摘要

PURPOSE: A method for fabricating a capacitor is provided to prevent an SiO2 film from being formed at a boundary between a polysilicon lower electrode and a Ta2O5 dielectric film by forming a diffusion stop film by use of TaN. CONSTITUTION: In a method for fabricating a capacitor of a semiconductor device, a lower electrode(11) is formed on a semiconductor substrate(10) by use of a polysilicon film. A TaN film(12) is formed on the lower electrode, and a Ta2O5 dielectric film(13) is formed on the TaN film. An upper electrode(14) is formed on the Ta2O5 film. After forming the Ta2O5 film, a N2O or O2 plasma process is performed at 300°C to 500°C, and then an annealing is performed during 30-40 munite at about 750°C in a furnace of O2 atmosphere.