高分子辅助化学溶液沉积法制备La_(0.7)Sr_(0.3)MnO_3/Si薄膜及电磁输运研究  

Transport Properties of La_(0.7)Sr_(0.3)MnO_3/Si Thin Films Grown by Polymer-assisted Chemical Solution Deposition

作　　者：刘其娅[1] 张敏 宋婷婷[2] 

机构地区：[1]西南交通大学超导与新能源研究开发中心,成都610031 [2]西华师范大学物理与空间科学学院,南充637002

出　　处：《人工晶体学报》2017年第4期621-626,共6页Journal of Synthetic Crystals

基　　金：四川省科技厅应用基础研究(2014JY0133);西华师范大学博士科研启动基金(412577)

摘　　要：利用高分子辅助化学溶液沉积法在Si(100)衬底上外延生长La_(0.7)Sr_(0.3)MnO_3薄膜。并利用X射线衍射仪结果、扫描电子显微镜结果和电阻率-温度曲线(ρ-T曲线)结果、磁电阻(MR)曲线结果对其晶体结构、表面形貌和电磁输运机制进行了研究。结果显示实验制备的La_(0.7)Sr_(0.3)MnO_3薄膜为赝立方钙钛矿多晶结构,薄膜表面均匀平滑,结晶性好,晶粒尺寸约为50~70 nm。随着温度降低,薄膜电输运机制从绝缘体行为向转变金属导电行为。金属绝缘转变转变点温度(T_(MI))随磁场的增加而升高,在0 T和1 T分别为T_(MI)=238K、246 K。电输运测试结果说明,低温(T<T_(MI))时,电子-电子的散射对薄膜的电导性能起主导作用,高温(T>T_(MI))时薄膜按照绝热近似的小极化子输运。Perovskite man-ganese oxides La0.7 Sr0.3 MnO3 （LSMO） thin films were epitaxial growth on Si （100） substrates by the polymer-assisted chemical solution deposition （PACSD） method. Microstructure, surface morphology and electronic transport behavior were investigated by X-ray diffraction （XRD） spectra, scanning electron microscope （SEM）, p-T curves and magnetoresistance （MR） of LSMO thin films. The surface of the LSMO thin films was smooth without crack. The LSMO thin films have a polycrystalline structure, and the grain size is about 50-70 nm. Metal-insulator transitions were observed in the samples. The transition temperature were 238 K and 246 K for 0 T and 1 T, respectively. The result of transport property suggested that the electron-electron scattering becomes dominant below the transition temperature, while the film has small polarons behavior of the adiabatic approximation above the transition temperature.

关 键 词：La0.7Sr0.3Mn O3薄膜 高分子辅助化学溶液沉积法 电磁输运性质 

分 类 号：O482[理学—固体物理]