Strain and lattice distortion in (110)-epitaxial orthorhombic TbMnO3 multiferroic thin films grown by pulsed laser deposition

Untwinned single phase thin films of multiferroic orthorhombic TbMnO3 are deposited by pulsed laser deposition on (1 1 0)-oriented NdGaO3 and YAlO3 substrates. X-ray diffraction measurements show that these films grow with a (1 1 0)-expitaxy on both substrates and the (1 1 0)-plane of a film shows a more square-like distortion imposed by the underlying substrate. Therefore, these films are under tensile strain along the [0 0 1] direction on NdGaO3. In the case of TbMnO3 on YAlO3, the film shows an unexpected tensile strain also along [0 0 1] contrary to expectations. X-ray reciprocal mapping confirms that with increasing thickness the film lattice parameters relax towards bulk values. In addition, an increase in mosaicity is also observed. (C) 2011 Elsevier B. V. All rights reserved.