微弧氧化沉积BaTiO_3介电薄膜的截面结构研究

Cross-section Structure of BaTiO_3 Film Synthesised by Micro-arc Oxidation

采用微弧氧化技术在工业纯Ti板表面沉积了BaTiO3薄膜,利用XRD、SEM、EPMA表征了薄膜表面及截面的物相组成、截面结构以及截面元素分布情况,并利用电容探测仪检测了薄膜的介电性能。结果表明:薄膜表面和截面均主要由四方相BaTiO3组成;薄膜截面可分为过渡层、致密层和疏松层,但各层元素含量不同;微孔的存在导致Ba、Ti、O三种元素在截面区域内的分布出现突变;测得薄膜在100 Hz下的介电常数和介质损耗分别为227.3和0.043。

BaTiO3 film was successfully fabricated by micro-arc oxidation on titanium plate.X-ray diffraction,scanning electron microscopy and electro-probe micro analyzer were used to characterize the film＇s crystalline structures and relative distribution on cross section.HP4284 capacitance prober was used to analyze the dielectric properties of the film.The results demonstrate that the micro arc-oxidation film is mainly composed of tetragonal BaTiO3 phases;film section can be divided into transition layer,dense inner layer and loose layer;the distribution of Ba,Ti,and O is waved on the cross section area owing to the existence of micro pore;and the film possesses both high dielectric constant of 227.3 and low dielectric loss of 0.043 at the frequency of 100 Hz.