溶胶-凝胶方法制备BiFeO_3薄膜及其铁电性质

Ferroelectricity of BiFeO_3 film prepared by sol-gel process

用溶胶-凝胶方法制备了BiFeO3薄膜,XRD研究表明薄膜呈随机取向,扫描电镜研究表明薄膜表面呈致密的多晶结构,薄膜与底电极之间没有互扩散。铁电性测试表明室温下的剩余极化强度为1.8μC/cm2,与低温下BiFeO3单晶的剩余极化相当。介电损耗呈弥散型转化,与薄膜中的Bi46Fe2O72相有关。

BiFeO3 film were prepared by sol-gel process. X-ray diffraction pattern indicates that the sample is random oriented. Scanning electron microscopy confirms that the film has a polycrystalline structure and there is no diffusion between the film and bottom electrode. Ferroelectric measurement shows that the remnant polarization of the film is 2.0 μC/cm2, which is comparable to the single crystal at low temperature. A diffused dielectric transition is identified which is attributed to the presence of Bi46Fe2O72 phase.