溶胶-凝胶法制备(Ba0.7Sr0.3)TiO3/LaNiO3异质薄膜及其结构和介电性质研究

采用改进的溶胶-凝胶方法在单晶Si(100)衬底上制备了介电性能优异的(Ba_0.7Sr_0.3)TiO₃/LaNiO₃异质薄膜.实验发现，在750 ℃下 、O₂气氛中晶化的LaNiO₃薄膜的电阻率最小.C-V与I-V特性测量表明(Ba_0.7Sr_0.3)TiO₃薄膜具有优异的介电性能，在频率为50kHz、零偏压下的相对介电常数ε_r>300，偏压为6V时漏电流密度J_L<1.2×10^-6A/cm². 关键词： xSr_1-x)TiO_３铁电薄膜')" href="#">(Ba_xSr_1-x)TiO_３铁电薄膜 ３底电极')" href="#">LaNiO３底电极 溶胶-凝胶法

Structures and dielectric properties of (Ba0.7Sr0.3)TiO3/LaNiO3 hetero-structure films prepared by sol-gel technique

(Ba_0.7Sr_0.3)TiO_３/LaNiO_３ he tero-structure films have been prepared on Si(100) substrate by an improved sol-gel technique. The structures and d ielectric properties for the films have been evaluated as a function of crystall ization temperature. It was found that LaNiO_３ films show the lowest resistivi ty after annealing at 750 ℃ in flowing O_２ for 30 min. C-V and I-V measureme nts revealed that the (Ba_0.7Sr_0.3)TiO_３ films have excellent diele ctric properties. The dielectric constant of the (Ba_0.7Sr_{0 .3})TiO_３ film annealed at 750 ℃ is larger than 300 under the measuring conditions of 50 kHz, zero bias voltage and room temperature. The maximum leakage current dens ity of the hetero-structure is about 1.2×１０^－６ A/cm^{２ under a bias voltage of 6 V.}