After a step of fabricating a MOS transistor (14) on a semiconductor substrate (11) and further steps up to bury a W plug (24), an Ir film (25a), an IrO.sub.y film (25b), a PZT film (26), and an IrO.sub.x film (27) are formed sequentially over the entire surface. The composition of the PZT film (26) is such that the content of Pb exceeds that of Zr and that of Ti. After processing the Ir film (25a), the IrO.sub.y film (25b), the PZT film (26) and the IrO.sub.x film (27), annealing is effected to remedy the damage to the PZT film (26) that is caused when the IrO.sub.x film (27) is formed and to diffuse Ir in the IrO.sub.x film (27) into the PZT film (26). As a result, the Ir diffused into the PZT film (26) concentrates at an interface between the IrO.sub.x film (27) and the PZT film (26) and at grain boundaries in the PZT film (26), and the Ir concentrations at the interface and boundaries are higher than those in the grains.