（Ba0.5Sr0.5）TiO3铁电薄膜的制备工艺及电学性质研究

采用溶胶 凝胶方法制备出纯立方钙钛矿相、介电性能和漏电流特性良好的 (Ba0 .5Sr0 .5)TiO3 铁电薄膜 .研究发现 ,随着烧结温度的升高 ,(Ba0 .5Sr0 .5)TiO3 薄膜纯度和结晶度增高 ,介电常数提高 ,漏电流密度降低 .在 75 0℃进行保温 1h热处理的薄膜性能较好且稳定 :在室温下测得薄膜介电常数为 2 5 0 ,介电损耗为 0 .0 30 ,漏电流密度为 6 .9× 10 -8A/cm2 .较高的介电常数、较低的漏电流密度可能源于良好的纯度和结晶度 .进一步研究表明 ,薄膜导电遵从空间电荷限制电流机制 .

(Ba0.5Sr0.5)TiO3 THIN FILM''S PREPARATION AND IT''S ELECTRIC CHARACTERISTICS

Ba 0.5Sr 0.5)TiO 3 ferroelectric thin films with pure perovskite structure and good dielectric and insulating properties were prepared by Sol-Gel processing. It was found that the purity and crystallinity and dielectric constant of (Ba 0.5Sr 0.5)TiO 3 ferroelectric thin films increased and the leakage current density decreased with the increase of temperature. Films treated at 750℃ for 1h showed good and stable properties with a dielectric constant of 250 and a dielectric loss of 0.030 and a leakage current density of 6.9×10 -8A/cm2. The high dielectric constant, low dielectric loss and leakage current density may originate from the good Purity and crystallinity of the films. The J-U characteristics of films indicated that the conduction of the films obeyed the mechanism of the space-charge-limited injection model.