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Ferroelectric BaTiO3 thin films were fabricated by metalorganic chemical vapor deposition (MOCVD) at atmospheric pressure. The ultrasonic spraying technique has been used to carry the source materials. The common solutions of barium-diethylhexanoate and diisopropoxy-titanium-bis-acetylacetonate in n-butanol were used as the starting materials. Since the concentration of sources can be controlled in the common solution, this method is more simple and precise than other CVD processes. The films had (110) preferred orientation with increasing temperature. The dielectric constant (ε) and the loss factor (tan δ) of thin film deposited at 550° C were about 250 and 0.1, respectively. The leakage current density was 10-5 A/cm2 at 0.1 MV/cm.

YBa 2 Cu 3 O 7−δ (YBCO) thin films were deposited using pulsed laser deposition (PLD) from modified melt-textured grown targets. As the laser energy density was increased, the surface of the films was covered with enhanced a-axis outgrowths. In order to determine the origin of these formations, the microstructures of films deposited at 2 and 4 J cm −2 were investigated using x-ray diffraction, transmission electron microscopy and high-resolution electron microscopy. It was found that a significant number of Y 2 O 3 inclusions were formed during the growth of c-axis-oriented films at 4 J cm −2 . These inclusions formed nucleation sites for the a-axis outgrowths. The formation of Y 2 O 3 inclusions was attributed to the Y-rich targets. In addition, the non-equilibrium characteristics of PLD and the enhanced ablation of Y-rich phases attributed to the increase of laser energy density led to these Y 2 O 3 inclusions. As for the a-axis outgrowth nucleation, it is considered that, due to the unstable growth conditions with a high flux density of incident vapour species and the strain induced by the surrounding c-axis films, the Y 2 O 3 inclusions would prefer the nucleation of a-axis grains.

Pb(Zr,, Til -do,( PZT) thin films were deposited on Si substrates using MgTiO, as the buffer layer and the electrical properties of those MFIS structures were investigated. PZT and MgTiO, films were made by MOCVD using ultrasonic spraying technique. Perovskite PZT films have been succesfully made at the substrate temperature of 550 to 600°C only when using MgTiO, buffer layer. AES depth profile analysis and RBS analysis revealed that there is no remarkable interdiffusion and no formation of reaction layer between PZT and MgTiO, and/or between MgTiO, and Si substrate. The capacitance-voltage (C-V) curves of the MFIS structure which were made with PZT and MgTiO, buffer layer have shown the hysteresis resulted from the ferroelectric switching of the PZT films.