Abstract
Pt-Ti alloy films were studied for use as a lower electrode of the ferroelectric lead zirconate titanate (PZT) thin film capacitor. Pt-Ti alloy films with different Ti/Pt atomic ratios were first prepared by rf sputtering. Subsequently, PZT thin films were deposited also by rf magnetron sputtering on the Pt-Ti alloy metals. The Ti/Pt ratio in the alloy was found to strongly affect the crystal structure formation and the composition of the PZT thin films. The Ti/Pt ratio range from 0.02 to 0.17 was shown to bring about a preferable perovskite-type structure and a reproducible constant composition. The effect of Ti atoms in the Pt-Ti lower electrode was discussed in connection with the Pb atom evaporation rate.