Enhancement of magnetoresistance in La0.75Ca0.25MnO3 thin films grown on Si(100) substrates

The enhancement of magnetoresistance (MR) in La0.75Ca0.25MnO3 thin films, g rown on Si (100) substrates by RF magnetron sputtering, is studied. The fil ms have single phase and show characteristics of a cubic perovskite structu re. The out-of-plane lattice parameters of films are reduced as much as 0.9 % compared with the one of the bulk sample. It is found that the maximum M R (Delta rho/rho (0)) of films are 0.34, 0.29 and 0.27 under the magnetic f ield of 1.5 T for each film with deposition temperatures of 700 degreesC, 7 50 degreesC and 800 degreesC, respectively. The correlation between the mag netotransport property and lattice parameters of films is discussed. It see ms that the enhancement of maximum MR can be attributed to the reduction of out-of-plane lattice parameters. (C) 2001 Elsevier Science B.V. All rights reserved.