Research Of Preparation And Magnetic Properties Of Magnetron Sputtered LSMO Films

La1-xSrxMnO3 (LSMO) has the pervoskite structure naturally, the ideal structureof LSMO is cubic structure, as the strain exists in LSMO film, the usual structures arethe rhombic and orthorhombic structure. Since the LSMO films exhibit the colossalmagnetoresistance effect, they have wide potential applications in the field ofinformation technique. The colossal magnetoresistance appears at temperature closeto the Curie temperature, and will reduce with the temperature being increased ordecreased quickly. Up to now, the typical composition where colossalmagnetoresistance could be seen is x=0.2~0.5, and most of these materials have theCurie temperature above room temperature, which promotes the research anddevelopment of room temperature devices, and in recent years becomes a veryinterested area in magnetic field. LSMO thin films were deposited by RF magnetron sputtering in this thesis, andthe main contents of the thesis are as follows: (1) Oriented La0.5Sr0.5MnO3 films were deposited on Si, LAO, and LSAT by RFmagnetron sputtering. With the help of XRD, AFM, XPS, and VSM, the structureand properties of La0.5Sr0.5MnO3 films were characterized. The results show thestructure and growth rate of La0.5Sr0.5MnO3 films are tightly related to the depositiontemperature and substrate material; La0.5Sr0.5MnO3 films have the flat surface, and thecrystal particles are intensely; the magnetic property of La0.5Sr0.5MnO3 films clearlyshows the spin glass behavior. (2) Oriented single LSMO films, oriented LSMO films with SrO or SrMnO3(SMO) buffer-layers were deposited on Si (100) by RF magnetron sputtering. Thefilms were characterized by XRD or RBS. The results demonstrate that byreasonable control of working parameters the single LSMO films with highpreferential orientation could be obtained; (100) and (110) oriented LSMO films withSrO or SrMnO3 (SMO) buffer-layers were achieved on traditional Si (100) substrate,and the diffusion phenomenon in the interface between La0.8Sr0.2MnO3 films andSMO buffer-layer or between SMO layer and Si (100) substrate is not seriouscomparing with that in La0.8Sr0.2MnO3 thin films with traditional multi-buffer-layers. - II -摘 要This further demonstrates that by applying SMO buffer-layers good interface can beattained, which offers the experimental references for accomplishing the integrating ofpervoskite oxides based devices with the traditional Si substrates.