Transport properties of La0.8Ca0.2MnO3 epitaxial films prepared by rf magnetron sputtering using soft targets

Abstract

Epitaxial La0.8Ca0.2MnO3 films have been prepared by the rf magnetron sputtering method using so-called ”soft” (or powder) targets instead of solid-state ones. The as-grown films have a highly oriented perovskite-like structure, a sharp metal–insulator transition in zero magnetic field at a temperature (Tp) near 220 K, and a temperature coefficient of resistance (TCR) of 900%. We found that a reduction in the film thickness leads to a shift of Tp in the low-temperature range and a significant suppression in the TCR value. The obtained films also exhibited an anisotropic temperature behavior of the magnetoresistance in a magnetic field of 1.5 T.