Nebulized spray deposition of Pb(Zr, Ti)O-3 thin films

Ultrasonic nebulized spray pyrolysis was employed in this study to deposit Pb(Zr, Ti)O-3 (PZT) thin films on n-type Si wafers using Ti(i-C3H7O)(4), Zr(n-C3H7O)(4), Pb(CH3COO)(2) . 3H(2)O as reactants. Experimental results revealed that the Pb content in the thin films plays an important role in the formation of the perovskite phase of PZT and is strongly dependent on deposition temperature. Composition measurements by electron spectroscopy for chemical analysis indicated that the Pb content is significantly deficient from stoichiometry for deposition at temperatures above 600 degrees C because of the high vapor pressure of PbO. In addition, because of the temperature dependence of phase change, the counterclockwise direction of the capacitance-voltage hysteresis of the films grown at 550 degrees C due to remnant polarization was opposite that of samples prepared at 630 degrees C. The leakage current densities bf the samples were found to decrease with an increase of growth temperature in the lower temperature range because of crystallinity improvement, and they deteriorated for samples grown at temperatures above 600 degrees C because of Pb deficiency.