低孔隙率阳极氧化铝膜的制备及其高绝缘特性

Preparation of anodic alumina films with low porosity and high insulation property

采用恒流阳极氧化法,制备出低孔隙率高绝缘特性的阳极氧化铝膜(AAO膜),研究乙二醇(EG)对AAO膜显微结构及其绝缘性能的影响。采用X射线衍射(XRD)、扫描电子显微镜(SEM)及绝缘性能测试仪对AAO膜的物相组成、显微形貌及其绝缘性能进行测试表征。结果表明,当EG体积分数为40%时,可获得孔隙率为1.0%的AAO膜,此时AAO膜绝缘电阻率达到最高值5.4×10^(13)Ω×cm;当EG体积分数为50%时,AAO膜的击穿场强达到最优值44.8 V/μm。草酸电解液中添加有机物EG可极大地降低AAO膜多孔层孔隙率,提高阻挡层厚度,大幅度提升AAO膜的绝缘性能。

Anodic alumina oxide（AAO） films with low porosity and high insulation property were prepared by galvanostatic anodization method. The effects of ethylene glycol（EG） addition on both the morphology and the insulation property of anodic alumina were evaluated. The composition, microstructure and insulation property of the AAO films were detected by X-ray diffracometry（XRD）, scanning electron microscopy（SEM） and insulation performance tester, respectively. The results show that when the volume fraction of EG is 40%, the porosity of the AAO film is only 1.0%, and the resistivity reaches 5.4×10^13 Ω×cm. When the volume fraction of EG is 50%, the breakdown strength of AAO film reaches 44.8 V/μm. The proper addition of ethylene glycol in oxalic acid aqueous could greatly reduce the porosity of the porous layer and increase the barrier thickness, which dominates the high density and great insulation property of the films.