中文摘要：

半金属材料Fe3O4是一种新型的功能自旋电子材料，由于其具有百分之百的自旋极化率而备受关注．但由于铁元素存在多种价态的氧化物，使得制备单一成分的Fe3O4非常困难，因而本文着重对磁控反应溅射制备单一成分的Fe3O4薄膜进行了研究，探索了晶化温度对薄膜结构的影响，并通过引入缓冲层Ta对其性能进行改善，得到了反应溅射制备半金属Fe3O4的最优条件．另外，通过对所制备的Fe3O4薄膜磁电阻效应的测试，发现多晶Fe3O4具有同单晶Fe3O4薄膜类似的负磁电阻效应，因此有望将其应用到自旋电子器件中．

英文摘要：

Half-metallic magnetic material Fe3O4 is a new kind of spintronics material, which can provide 100% spin polarization. The Fe element has many electronic valences, so the pure Fe3O4 is difficult to prepare. Therefore, in this paper we mainly focused on finding the optimal way to fabricate pure Fe3O4 film. Half-metallic Fe3O4 films grown on Si （100） substrates were prepared by DC magnetron reactive sputtering. The annealing temperatures were investigated carefully, and the polycrystalline Fe3O4 films fabricated on Ta buffer layer shown better properties than the film directly sputtering on Si substrate. The optimum condition for the formation of polycrystalline Fe3O4 under DC magnetron reactive sputtering was found. The negative magnetoresistance of polycrystalline Fe3O4 was also tested, and showed a very weak saturation trend as the singlecrystalline Fe3O4 films.