镍掺杂铁酸铋薄膜的电磁性能研究

Study on Electric and Magnetic Properties of Ni-doped BiFeO_3 Films

利用溶胶-凝胶工艺在ITO/玻璃衬底上制备了纯相铁酸铋(BiFeO3,BFO)和镍掺杂铁酸铋(BiFe0.9Ni0.1O3,BFNO)薄膜。X-射线衍射(XRD)测试表明纯相和镍掺杂铁酸铋分别为扭曲钙钛矿结构和四方相结构,具有不同的空间对称性。镍掺杂后(012)衍射峰宽化,峰强变弱,说明晶粒变小,并由原子力显微镜(AFM)测试得到验证。镍掺杂铁酸铋具有更大的介电常数和较小的漏电流。铁电测试仪和振动样品磁强计(VSM)测试结果表明镍的掺入可以进一步提高铁酸铋的室温铁电性和铁磁性。

Pure BiFeO3 and Ni-doped BiFeO3 thin films were fabricated on indium tin oxide （ITO）/glass substrates by sol-gel process. XRD analysis indicated that the pure BiFeO3 and Ni-doped BiFeO3 thin films presented single rhombohedral and tetragonal structure with different space symmetry. The （012） diffraction peak became weak and broaden with Ni doped, which indicated the grains size became small were confirmed by atom force microscope （AFM）. The dielectric constant increased and leakage current decreased with Ni doped. Ferroelectric tester and vibrating sample magnetometer （VSM） showed the room-temperature ferroelectricity and ferromagnetism was enhanced with Ni doped.