Study on the orientation degree of Pb 1 − xLa xTiO 3 thin films by the rocking curve technique and its morphological aspects

Abstract

Thin films of perovskite-type materials such as PbTiO 3, BaTiO 3, (Pb,La)TiO 3, (Pb, La)(Zr,Ti)O 3, KNbO 3, and Pb(Mg,Nb)O 3 have been attracting great interest for applications like non-volatile memories, ultrasonic sensors and optical devices. Thin film should be epitaxially grown or at least highly textured since the properties of this anisotropic material depend on the crystallographic orientation. For optical devices, in particular, an epitaxial thin film without defects are essential to reduce optical propagation losses. Pb 1 − x La x TiO 3 (PLT) where x = 0, 13 and 27% thin films were prepared by a chemical method (polymeric precursors method), and deposited by the spin coating technique onto substrates of SrTiO 3 (STO) and LaAlO 3 (LAO). The films were then heat treated at 500 °C in a controlled atmosphere of O 2. The orientation degree of the thin films was obtained from rocking curve technique, by means of X-ray diffraction analysis. A microstructural study revealed that the films were crack-free, homogeneous and have low roughness.