Quantitative texture analysis applied to the study of preferential orientations in ferroelectric thin films

The occurrence of preferred crystallographic orientations, or texture, is a determinant factor of the behaviour of polar materials, like ferroelectric thin films. This is the reason why numerous works have been focused in the preparation of highly oriented films for pyroelectric sensors and electrom echanical applications. Traditionally, preferred orientations were determin ed by the analysis of the main reflections obtained by X-ray diffraction, w hich only in some cases are characteristic of the texture of the material. Regardless of the interest of this subject, the quantitative texture analys is of ferroelectric thin films has not been systematically applied. This co nsists in the measurement of pole figures with a goniometer, and the determ ination of the orientation distribution function. In this work we summarise briefly the principles of the quantitative texture analysis and we demonst rate its application to the study of different ferroelectric thin films: La and Ca modified lead titanate (PTL and PTC) and lead zirconate titanate (P ZT). This method allows the study of the characteristics of the type of tex ture and the identification of the different components that contribute to the final texture of the material. An indicative value of the texture stren gth is also obtained for both the ferroelectric film and the substrate laye rs. This information allows us the study of the process that leads to the o rientation in thin films, and to obtain correlations between texture and ph ysical properties.