Sol-gel法制备La_(1-x)Sr_xMnO_3巨磁电阻薄膜材料

Giant Magnetoresistive Nanocrystalline Films of La 1- x Sr x MnO 3 Prepared by Sol gel Method

利用ｓｏｌ－ｇｅｌ法在单晶硅Ｓｉ（１００）衬底上，制备了钙钛矿Ｌａ１－ｘＳｒｘＭｎＯ３（ＬＳＭＯ）低织构纳米晶薄膜．考察了制备条件对ＬＳＭＯ成相、晶粒的粒度和表面形貌的影响，研究了其磁特性和磁电阻性能．结果表明，Ｌａ０．７Ｓｒ０．３ＭｎＯ３薄膜磁电阻效应在相当宽的温度范围内不随温度改变，在６Ｔ磁场中室温下磁电阻比ＭＲ值可达－３０％

The nanocrystalline films of perovskite like manganites La 1- x Sr x MnO 3(LSMO, x= 0￣0.6 ) on the single silicon(100) substrates have been fabricated by sol gel method. The annealing dependence of the phase formation, grain size and film morphorlogy have been investigated. The measurement on the magnetoresistance of the films with standard four electrode method shows a widened peak of resistance for each sample due to the boundary effect and a MR value of about -30% at room temperature in 6 T magnetic field for the sample La 0.7 Sr 0.3 MnO 3.