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利用金属有机物分解法在非晶石英衬底上成功地制备了具有 (202)择优取向的多晶 La1－ x－SrxMnOz薄膜。原子力显微镜观察显示薄膜具有疏松的结构缺陷。在室温下，观察到薄膜磁电阻随外加磁场变化具有优良的线性特征， 10 kOe磁场下，磁电阻值达到 5％。在 77 K低温下，薄膜具有显著的低场磁电阻效应， 2 kOe磁场下的磁电阻值达到 11％。薄膜的电阻－温度关系具有平缓的金属－绝缘体转变，转变温度远低于其居里温度；在 8 kOe磁场下，薄膜的磁电阻随温度下降而单调上升。上述薄膜的磁输运特性与其结构缺陷 (包括晶界及疏松 )有关。
A polycrystalline La1-x-SrxMnOz thin film with (202) preferred orientation was successfully prepared on an amorphous quartz substrate by a metal-organic decomposition method. Atomic force microscopy showed that the film had loose structural defects. At room temperature, it is observed that the magnetoresistance of the thin film has excellent linearity with the change of the applied magnetic field, and the value of the magnetoresistance reaches 5% under the magnetic field of 10 kOe. At 77 K, the film has a significant low field magnetoresistance effect and a magnetoresistance of 11% at a 2 kOe magnetic field. The resistance-temperature dependence of the film has a gentle metal-insulator transition with a transition temperature well below its Curie temperature. With a magnetic field of 8 kOe, the magnetoresistance of the film increases monotonically with decreasing temperature. The magnetic transport properties of these films are related to their structural defects, including grain boundaries and porosity.