Structure and anisotropic magnetoresistance of sol–gel spin coating synthesized La0.67Ca0.33MnO3 films on various substrates

Perovskite manganese oxides, as strongly correlated systems, exhibit a rich interplay of competing metallic and insulating phases that give rise to diverse physical properties, including anisotropic magnetoresistance (AMR), ferromagnetism, and ferroelectricity. This unique behavior has made these materials a subject of intense research in recent years. However, the practical application of manganese oxide-based AMR devices faces significant challenges, such as limited accuracy under low magnetic fields, operational temperatures far from room temperature, and a high preparation threshold, which collectively restrict their viability for angle sensor technologies. In this study, we fabricated La 0 . 6 7 Ca 0 . 3 3 MnO 3 (LCMO) films on four distinct substrates — LaAlO 3 (LAO), NdGaO 3 (NGO), (LaAlO 3 ) 0 . 3 (SrAlTaO 6 ) 0 . 7 (LSAT), and SrTiO 3 (STO) — using a sol–gel spin coating technique. The wet films were rapidly sintered at 1 1 0 0 ∘ C in a tubular furnace, yielding LCMO/LAO, LCMO/NGO, LCMO/LSAT, and LCMO/STO samples. We systematically investigated the impact of substrate choice on the structural, morphological, and magnetotransport properties of the films. Among the samples, the LCMO/LAO film demonstrated exceptional magnetoresistive performance, achieving a magnetoresistance (MR) of 63.6% at 273 K. Furthermore, by optimizing interfacial strain, we enhanced the AMR performance of LCMO/NGO films to − 28.7%. These findings not only advance the understanding of strain-mediated MR in perovskite manganites but also pave the way for the application of La 1 − x Ca x MnO 3 thin films in directional magnetic sensors, significantly broadening their potential for room–temperature device integration.