(BiFeO_3)_(25)/(La_(0.7)Sr_(0.3)MnO_3)_(25)多层膜的光学和电学性质

Optical and electrical characterization of (BiFeO_3)_(25)/(La_(0.7)Sr_(0.3)MnO_3)_(25) multilayered thin films

采用射频磁控溅射方法在(001)SrTiO3衬底上制备(001)取向的(BiFeO3)25/(La0.7Sr0.3MnO3)25多层膜.光学测试结果表明,1.3—2.1eV范围内,相对于衬底而言多层膜光吸收增强;BiFeO3的带隙为2.7eV.另外,结合绝缘介质导电模型分析了所测得的电流-电压数据,在所测试的温度及电压下,所制备的(BiFeO3)25/(La0.7Sr0.3MnO3)25多层膜的导电机理由空间电荷限制电导主导.

（001） oriented（BiFeO3）25/（La0.7Sr0.3MnO3）25 multilayered thin films are fabricated on （001）SrTiO3 substrate by rf-magnetron sputtering.UV-vis absorption spectrum analysis in a photon energy range of 1.2—6.4 eV is carried out,and the result shows that in a range of 1.3—2.1 eV the absorption is enhanced compared with that on SrTiO3 substrate.And the optical band gap of BiFeO3 is around 2.7 eV,which is in accordance with other reportsed results very well.Furthermore,the current-voltage curves are measured in a temperature range of 100—300 K,and the analyses according to several dielectric conduction models exhibite that the space-charge-limited conduction is dominated in the fabricated （BiFeO3）25/（La0.7Sr0.3MnO3）25 multilayered thin films.