Fabrication, dielectric and ferroelectric properties of Ba_(0.6)Sr_(0.4)TiO_3 film with preferred orientation

摘要

Ba_(0.6)Sr_(0.4)TiO_3 films were fabricated by RF magnetron sputtering method. The X-ray diffraction (XRD) showed that the preferred orientation of films growing on platinum Si substrates can be tailored by sputtering pressure. The processing parameters such as sputtering pressure and substrate temperature were optimized to obtain a developed perovskite film with (110) preferred orientation. The polarization hysteresis loops and permittivity-voltage curves of the (110)-oriented film have been investigated,which demonstrated that the film is in ferroelectric phase at room temperature. Besides, it had excellent fatigue properties without polarization reduction after about 1010 switch cycles, and showed low leakage current (10~(-9)-10~(-7) A/cm~2) within an applied voltage of 5 V. Finally, the leakage current mechanism was studied.