Substrate effect on the crystal structure and ferroelectricity of low-temperature-deposited Pb(Zr, Ti)O3 thin films by metalorganic chemical vapor deposition

Tetragonal Pb(Zr0.35Ti0.65) O-3 thin films were deposited at deposition temperatures ranging from 395 degreesC to 510 degreesC on (111) Pt/Ti/SiO2 /Si, (111) Ir/ TiO2 / SiO2 / Si, and (100) Ru/ SiO2 / Si substrates by metalorganic chemical vapor deposition. When the deposition temperature was above 415 degreesC, the remanent polarization (Pr) and the coercive field (Ec) were almost the same for the Pb( Zr0.35Ti0.65) O-3 thin films deposited on these substrates. This means that the electrical properties were not significantly affected by the type of substrate above 415 degreesC. However, at 395 degreesC, the film deposited on the (111) Pt/ Ti/ SiO2 / Si substrate showed a larger Pr value than those on the (111) Ir/ TiO2 / SiO2 / Si and (100) Ru/ SiO2 / Si substrates. The lower crystallinity of the films deposited on the (111) Ir/ TiO2 / SiO2 / Si and (100) Ru/ SiO2 /Si substrates, due to the oxidation of the Ir and Ru surfaces before starting film deposition, thwarts the attainment of good ferroelectricity. (C) 2003 American Institute of Physics.