Strain effect on the transport properties in low-doped La0.9Hf0.1MnO3 epitaxial films

La0.9Hf0.1MnO3 thin films with different thicknesses are epitaxially grown on SrTiO3 (100) single-crystal substrates by using pulsed laser deposition. X-ray diffraction shows that these thin films are of single phase and highly epitaxial. The influence of film thickness on the resistivity and metal-insulator transition is studied in various magnetic fields. The magnetoresistive properties of these La0.9Hf0.1MnO3 films are similar to those of other doped LaMnO3 manganites. The metal-insulator transition temperature (T-p) is developed by decreasing the film thickness from 400 to 150 nm. The T-p associated with conductivity increases as the thickness is reduced. The effect of lattice deformation and oxygen deficiency is analyzed to explain the observed phenomena. (c) 2008 American Institute of Physics.