Functional oxide based on the perovskite structure are the subject of intense research in the field of micro- and nanoelectronics. However, in contrast with semiconductor films, oxide layers are much more difficult to grow with a high crystalline quality level which results in very broad and complicated reciprocal space features. Therefore it is often extremely challenging to obtain reliable information concerning the nanostructure of oxide layers using X-ray diffraction (XRD).

In this communication we will adress some important issues that can be encountered in the study of RNiO₃ perovskites (R = rare-earth). These compounds are extremely difficult to stabilize because of the less stable 3+ oxidation state of Ni. A possible way to stabilise RNiO₃ phases is to use epitaxial strain. It can hence be expected that strain will profoundly affect the structure and microstructure of these epitaxial films.

Using the particular example of SmNiO₃ grown on different substrates (SrTiO₃, LaAlO₃), we will show in this communication that using different complementary X-ray scattering techniques allows us to access a wealth of information concerning the defect structure of the films:

- the contribution of chemical and mechanical effects to the lattice parameter can be rigorously separated using laboratory based X-ray reciprocal space mapping and synchrotron grazing incidence diffraction.

- the effect of relaxation-induced misfit dislocations are investigated using high resolution synchrotron XRD (HRXRD). The presence of misfit dislocations induces asymmetrical longitudinal profiles which are quantitatively analyzed using a semi-kinematical scattering model based on B-spline functions.

- highly localized strain fields due to a particular type of planar faults (Ruddlesden-Popper faults) are studied by HRXRD. These defects give rise to extended diffuse scattering in reciprocal space which can be analyzed using a recently developed phenomenological scattering model.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/11641 must be provided.