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Barium titanate (BaTiO3) thin films grown by the metalorganic chemical vapor deposition (MOCVD) technique on MgO substrates have been investigated by second-harmonic generation at an incident wavelength of 1.064 μm. Transmission electron microscopy was used to show that substrate quality and pretreatment (annealing) has a strong influence on microstructure and optical properties of these films due to nucleation effects during MOCVD growth. Angular dependence of second-harmonic signal indicates both a- and c-textured growths in this film/substrate system. Stress-induced stabilization appears to determine the orientation of the microcrystallites in the films. Corona poling does not result in a preferred orientation of the film. Effective d coefficients as high as 2.13 pm/V have been obtained from as-grown films.

The implementation of ferroelectric thin films in advanced semiconductor devices is near; facile integration at ULSI geometries requires chemical vapor deposition (CVD) process technology. The low volatility and thermal stability of many of the existing source reagents has driven the development of liquid source CVD, in which composition is set by volumetric metering of liquids followed by flash vaporization. The methodology as well as early results for Ba1- x Sr x TiO3, Pb1- x (La x Zr1- y Ti y )1- x /4O3 and SrBi2Ta2O9 thin films, which are among the best reported for any deposition method, will be reviewed. These results establish liquid source CVD as a leading candidate to become the predominant deposition technology enabling the integration of ferroelectric thin films in ULSI devices.

Epitaxial BaTi3 films have been grown on NdGaO3 [100] substrates by reduced pressure MOCVD for the first time. The substrate temperature was 1000 °C and the total pressure was 4 Torr. Electron and x-ray diffraction measurements indicate highly textured, single phase films on the NdGaO3 substrate which are predominantly [100], with [110] also present. TEM and selected area electron diffraction (SAED) indicate two specific orientational relationships between the [110] and the [001] diffraction patterns.