Background signal from substrates in characterizations of magnetic thin films

A LSMO thin film was fabricated on SrTiO3 substrate by radio frequency magnetron sputtering method. The influences of the background signal from SrTiO3 substrate on magnetic measurements were studied. Wide differences between the cases before and after subtracting the substrate background were observed. The magnetic properties of some commercial substrates, such as Si, c-plane Al2O3, (100) SrTiO3, (100) MgO, fused SiO2 glass and (100) GaAs, were also characterized.