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LaNiO 3 (LNO) thin films were deposited by radio frequency magnetron sputtering on n-type Si (100) wafers at room temperature (RT). The as-sputtered LNO thin films were amorphous and had very high RT electrical resistivity even after post-annealing at 800 °C. The amorphous as-sputtered LNO films could be transformed to polycrystalline LNO films in rhombohedral phase by heating at 400 °C in an O 2 atmosphere at pressure ranging from 1.5 to 8.0 MPa. Very low RT resistivity of LNO films were obtained by this high oxygen-pressure processing. The lowest value was as low as 1.09 × 10 − 4 Ω cm by processing at oxygen pressure of 8 MPa. Such preparation of LNO thin films is compatible with the Si-based readout integrated circuits. Highly (100)-oriented perovskite structure of Pb(Zr 0.52 Ti 0.48 )O 3 thin films was formed on this rhombohedral phase LNO, and good ferroelectricity could also be obtained on these HOPP-processed rhombohedral phase LNO films.

The Pb1−xLaxTiO3 (PLT) ferroelectric thin films on Pt/Ti/SiO2/Si(1 0 0) substrates were fabricated by a sol–gel process. The infrared optical properties of PLT thin films with x=0.1, 0.2, 0.25 on platinized silicon Pt(1 1 1)/Ti/SiO2/Si(1 0 0) substrates were studied by infrared spectroscopic ellipsometry (IRSE) technique in the wavelength region from 2.5 to 12.6 μm. The infrared optical constants were obtained by fitting the IRSE data using a classical dielectric function model. The refractive index increases, and the extinction coefficient decreases as wavenumber increases in the measured infrared region. The refractive index of PLT thin films decreases as the La contents increase in the films.

Highly (100)-oriented LaNiO3 (LNO) films directly on Si substrates were prepared by a simple chemical solution technique using lanthanum nitrate and nickel acetate as the start material sources. Highly (100)-oriented PbZr0.30Ti0.70O3 (PZT30/70) thin film was fabricated subsequently on the LNO-coated Si substrates using a modified sol-gel method. The orientation of the PZT and LNO thin films was characterized by X-ray diffraction (XRD). The resistivity of the LNO thin film at room temperature (300 K) is 7.6×10−4 Ωcm. The remmant polarization (Pr) and coercive field (Ec) of the Pt/PZT/LNO/Si capacitor were 10.5–16.8 μC/cm2 and 20.5–31.6 kV/cm with the variation of electric field (100–200 kV/cm). The values of dielectric constant and dissipation factor of 10 kHz were 700 and 0.019, respectively. After 108 switching cycles, the net-switched polarization values of the capacitor drop to 95, 62, and 37% of their initial values under different electric fields ranging from 100 to 200 kV/cm, respectively.

PbZr0.5Ti0.5O3 thin films have been prepared on Pt (111)/Ti/SiO2/Si substrates by a modified sol–gel technique. The PZT films were annealed layer by layer using a rapid thermal annealing (RTA) method during the spin-coating process. A novel route was used to obtain PZT films with different single-annealed-layer in thickness from the same precursor solution. It is found that the degree of (111) orientation of the films increases with the reduction thickness of single-annealed-layer. As the thickness of single-annealed-layer drops to 40 nm, the film shows a high degree of (111) preferred orientation. The decrease of single-annealed-layer thickness also leads to the increase of the remanent polarization and the dielectric constant.

Bi 3.25 La 0.75 Ti 3 O 12 (BLT) thin film was prepared on quartz substrates using chemical solution deposition. The sign and magnitude of both real and imaginary parts of third-order nonlinear susceptibility χ (3) of the BLT thin film have been determined by the Z-scan technique performed at 800 nm with a femtosecond laser. The nonlinear refractive index coefficient γ and the nonlinear absorption coefficient β of the BLT thin film are − 1.915 × 10 − 12 cm 2 / W and − 6.764 × 10 − 8 m/W, respectively, the real part and imaginary part of the third-order nonlinear susceptibility χ (3) of the BLT thin film are − 5.81 × 10 − 18 m 2 / V 2 and − 1.31 × 10 − 18 m 2 / V 2 , respectively. Both the real and the imaginary parts of the third-order nonlinear susceptibility χ (3) contribute to the nonlinearity of the film. These experimental results show that BLT thin film is a promising material for applications in nonlinear optical devices.