Abstract
PbZrO3 (PZ) films of different thicknesses have been grown by metalorganic chemical vapor deposition on SrTiO3 (STO) substrates. The structure of the films was determined by x-ray diffraction and transmission electron microscopy. At the deposition temperature, the growth is cube on cube and is therefore heteroepitaxial. During cool down, PZ goes through a phase transformation from paraelectric to antiferroelectric at the Curie temperature and its cubic structure is stretched to orthorhombic. This results in domain formation in the PZ films corresponding to the different stretching directions. At room temperature, the thin PZ film consists of at least two different (120) domain variants and the thin-film–substrate relation can be described as (120)[002]PZ//(100) [00] STO for one of these variants. By etching down a thick film, it was observed that ~260 nm is the threshold thickness, above which two additional different (002) domain variants appear in addition to the (120) domain variants. For one of the (002) domain variants, the thin-film–substrate relation can be described as (002)[100]PZ//(100)[011] STO. The surface morphology of the thick films, studied by scanning electron and atomic force microscopy, is partly covered with pyramids. These pyramids can originate from both (120) or (002) domains and are due to a higher growth rate of these two planes compared to the rest of the layer. A suggestion is made for pyramid-facet indexing for both domains.