Abstract
La1-xSrxMnO3 (x=0.3) thin films with thicknesses of 100-900Å were grown epitaxially on SrTiO3 (l00) and (110) substrates by magnetron sputtering. The ferromagnetic transition temperatures (Tc) of the films ranged from 140 to 330 K, depending on the growth conditions and film thickness.This variation in the Tc values of the films was possibly due to their oxygen deficiency. As a general trend,larger magnetoresistance (MR) ratios were obtained for films with lower Tc values (lower hole concentrations).Ultra-thin film of 100Å with Tc of 140 K exhibited relatively large magnetoresistance (MR) with an MR ratio (Δρ/ρ0) of 71% at H= 18 kOe.
