Optical properties of PZT thin films by spectroscopic ellipsometry and optical reflectivity

摘要

Optical properties of PbZr_(0.3)Ti_(0.7)O_3 (PZT) thin films have been investigated using variable angle spectro-seopic ellipsometry (VASE) and near-normal spectroscopic reflectivity (NNSR). The measurements were carried out in the spectral range 1-6 eV up to 500 ℃ by VASE and in the range 1 - 12 eV by NNSR at room temperature. The PZT films of two different thicknesses (730 and 900 nm) were deposited on platinized Si substrates by sol-gel (CSD) technique. VASE and NNSR data were rnsimultaneously evaluated to obtain the optical response functions (e.g. complex refractive index, dielectric function) and thicknesses of these films. Several dispersion models were used to fit the experimental data and determine the optical response functions and geometric parameters of the thin films. The absorption edge of PZT films was found about 3.2 eV and its temperature dependence was also determined. These results werere compared with the Kramers-Kronig analysis.