Structure and Magnetic Properties of Nd0.88MnO3 Films Grown on SrTiO3 (100) Substrates by Liquid-Injection MOCVD

Abstract

In this study, we investigated the structure and magnetic properties of Nd0.88MnO3 (NMO) perovskite thin-film layers by liquid-injection metalorganic chemical vapor deposition (MOCVD) tried on SrTiO3 (STO) (100) substrates. The structural examinations showed that the growing film was amorphous. It changed to the crystalline phase after being annealed at 900°C in air for 24 h. A minor secondary phase identified as Mn3O4 appeared. The film was subjected to in-plane (IP) tensile stress leading to a contraction of the film’s out-of-plane (OOP) lattice parameters. The orientation relationships for the film structure are described near the interface as $$ \left[ {10\bar{1}} \right] $$ NMO// $$ \left[ {100} \right] $$ STO and $$ \left[ {010} \right] $$ NMO// $$ \left[ {001} \right] $$ STO. The NMO thin film showed ferromagnetic ordering with a transition temperature TC = 85 K. The large bifurcation between ZFC and FC curves with a cusp at Tf = 53 K; and an irreversible temperature Tirr = 48 K proves that the spin-glass behavior with long-range ferromagnetic order (Mn3+-O2−-Mn4+) co-exists in NMO thin films. The magnetic easy axis corresponded to the surface normal.