Texture Analysis in LD-MOCVD Processed Thin Film Giant Magnetoresistant (LaM)MnO₃ Materials

Abstract

Thin films of La_0.67M_0.33MnO₃ (M=Sr), LSMO were deposited on three different substrates of LAO, Sapphire, and Y-ZrO₂ (YSZ) using metal–organic chemical vapor deposition methods. The effect of texture and orientation on the resistance (0 and 6T) and magnetoresistance (MR) of (LSMO) thin films on various substrates has been investigated. X-ray pole figures were measured using Philips X’Pert X-ray diffractometer equipped with the PopLa analysis package. A direct correlation was observed between the lattice mismatch strain and the structure of the thin film growth. LSMO/LAO seems to be the most perfect system for epitaxial growth due to the negligible lattice-mismatch (∼2%). The dominant orientation changes for the films deposited on LAO [100] and LAO [110] substrates while the transition temperature from ferromagnetic to paramagnetic state of the film on LAO [100] is 50 K higher than that of the film on LAO [100]. The MR data and TMI temperature were measured using standard 4-point resistivity devices and SQUID.