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Figure 10. XRD pattern in the range 45-50° of 150-nm-thick Pr05Ca05MnO3 films on (a) SrTiO3 and (b) LaAlO3. Note the difference in the out-of-plane lattice parameter to the strain effects.

subsequently the Mn-O-Mn bond angle) was calculated to be 0.393 nm for STO and 0.384 nm for LAO [112].

Lattice mismatch (i.e., the difference of parameters between the film and the substrate) influences not only the parameters of the film but also the texturation (or epitaxy), that is, the in-plane alignments. Usually, changes in the in-plane orientation are observed only when the mismatch is small (e.g., LCMO on LAO [113] and is not realized on YSZ [114] or on MgO [115]). Textured La2/3Sr1/3MnO3 films were obtained on Si when buffer layers [17] were used. La0.7Ca0.3MnO3 was grown using a buffer layer of CeO2 [116] and LSMO with a buffer of YSZ [16] or a double layer Bi4Ti3O12/SiO2 [92]. A highly conducting diffusion barrier layer of TiN has also been utilized recently as a buffer layer [118]. This progress is interesting for technological reasons especially when using Si substrates.

A surprising effect of lattice mismatch is related to the orientation of the films, especially those that crystallize in an orthorhombic perovskite cell. This was first seen on YMnO3 [119], which is [010]-oriented on SrTiO3

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