Nebulized Spray Deposition of Pb ( Zr , Ti )  O 3 Thin Films

Abstract

Ultrasonic nebulized spray pyrolysis was employed in this study to deposit Pb(Zr, Ti)03 (PZT) thin films on n-type Si wafers using Ti(i-C3H70)4, Zr(n-C2H70)4, P'O(CH3COO)2 3H20 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°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°C due to remnant polarization was opposite that of samples prepared at 630°C. The leakage current densities of 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°C because of Pb deficiency.

Fabrication of Ferroelectric Pb(Zr,Ti)O3 Thin Films by Spray Metalorganic Chemical Vapor Deposition

“…Similar techniques, such as spray pyrolysis or spray deposition, have been investigated for various materials. [12][13][14][15] However, these techniques require large amounts of carrier gas 12,13) and/or vacuum conditions 14) for the atomization of liquid precursors and film deposition. Although our deposition method is indeed a kind of spray pyrolysis technique, it is unique because our method uses a MOCVD precursor solution and no carrier gases or vacuum is needed.…”