The effect of Sr concentration on resistive switching properties of La 1 − x Sr x MnO 3 films

La1−xSrxMnO3 (LSMO, x=0.1, 0.3, and 0.5) thin films were prepared on Pt/Ti/SiO2/Si substrates using a radio frequency magnetron sputtering technique at a substrate temperature of 450°C. The effects of Sr contents on the physical, chemical, and electrical properties of films were systematically investigated. X-ray diffraction results showed that the growth orientation and crystallinity of films were affected by Sr content. The Mn valence transition was analyzed using X-ray photoelectron spectroscopy. The conversion of Mn3+ valence to Mn4+ with increasing Sr2+ concentration generated more Mn3+–O2−–Mn4+ bonds, and caused initial resistance change of LSMO films. The largest resistive switching of the La0.7Sr0.3MnO3 film having a (110) plane preferred orientation is discussed.