Composition control of Pb(ZrxTi1-x)O-3 thin films prepared by metalorganicchemical vapor deposition

PbO, ZrO2, TiO2 and Pb(ZrxTi1-x)O-3 (PZT) films were prepared by metalorgan ic chemical vapor deposition (MOCVD) using Pb(C11H19O2)(2), Zr(O . t-C4H9)( 4), Ti(O . i-C3H7)(4) and O-2 as source materials. The deposition rates of the constituent metals of Pb(ZrxTi1-x)O-3 (PZT) film were investigated as f unctions of the input gas flow rate of the source materials and the deposit ion temperature. Composition ratios of the PZT film became constant when th e Ar carrier gas flow rate of the Pb source was above 100 cm(3)/min at 500 degrees C. This suggests that a self-correcting composition region exists f or this input gas composition at 500 degrees C. The deposition rates of eac h of the constituent metals of the PZT films were quite different from thos e in the corresponding single-oxide films, PbO, ZrO2, and TiO2 films. There fore, the composition ratio of the PZT film could not be estimated from the deposition rates of the corresponding single-oxide films. The deposition t emperature dependence of the deposition rates of Ti and Zr in the PZT films was almost the same. This results in the Zr/(Zr+Ti) ratio being independen t of the deposition temperature. However, the deposition behavior of Pb was different from those of Ti and Zr. Therefore, the Pb/(Pb+Zr+Ti) ratio must be adjusted by changing the input gas flow rate of the Pb source when the deposition temperature is changed.