Effect of heat treatment on preferred orientation of sol-gel deposited PZT thin films

PZT films were fabricated using the addition of 10% excess of Pb to the starting solution and spin coating onto Pt/Ti/SiO₂/Si substrates. The effect of the thickness on texture of the films was investigated, and it is clear that the (100) texture gradually increases and the (111) texture decreases with increasing film thickness. A Pt_xPb intermetallic metastable phase was observed by X-ray diffraction, and it is found that the position of this peak shifted from 2θ = 38.30°(d = 0.2348 nm) to 2θ = 37.10°(d = 0.4213 nm) with increasing firing temperature from 350 °C to 550 °C. The (111) preferred orientation in the PZT film was not attributed to the metastable Pt_xPb phase. The temperature of pyrolysis of the PZT films influences the preferred orientation of the film: 250 °C favored a (111) orientation, whereas 400 °C favored a (100) orientation.